Integrally Combined Current Carrier Circulation Chamber and Frame for Use in Unipolar Electrochemical Devices

ABSTRACT

Disclosed is an integrally combined electrical current carrier, circulation chamber and frame (CCF) formed as a single or double part (CCF) for use in unipolar electrochemical devices. The CCF is structured to define an internal circulation chamber for circulation of electrolyte, products, and reactants as well as apertures which form flow passageways when the filter press device is assembled. Affixed on opposed surfaces of the CCFs are electrically conductive planar electroactive structures which are in electrical contact with the CCF. The circulation chamber is formed by the depth of the CCF itself between opposing electroactive structures. Multiple CCFs are assembled and compressed together to form the filter press electrolyser apparatus. When power is applied to the CCFs and electroactive structures, the reactants, once they flow into the circulation chamber with the electrolyte, undergo redox reactions to produce products that are collected and exit the electrolyser in upper flow pathways.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional App. No.63,053,264; U.S. application Ser. No. 17/544,176 (Issued as U.S. Pat.No. 11,560,634); U.S. application Ser. No. 16/994,125 (Issued as U.S.Pat. No. 11,225,724); and U.S. application Ser. No. 18/080,583. Thepresent application is a continuation application of U.S. applicationSer. No. 18/080,583, filed on Dec. 13, 2022, which is in turn acontinuation application of U.S. application Ser. No. 17/544,176, filedon Dec. 7, 2021, which is itself a continuation application of U.S.application Ser. No. 16/994,125, filed Aug. 14, 2020, and which claimspriority to U.S. Provisional App. No. 63,053,264, filed Jul. 17, 2020.

The entire content of U.S. Provisional App. No. 63,053,264; U.S.application Ser. No. 17/544,176; U.S. application Ser. No. 16/994,125;and U.S. application Ser. No. 18/080,583 is incorporated herein byreference.

FIELD

This disclosure relates to an electronically conductive novel structurefor use in electrochemical devices such as electrolysers, consisting inan integrally combined current carrier, circulation chamber, and framestructure formed as a single part (“CCF”), suitable for use in theelectrolysis of an alkali aqueous solution of water and an alkali metalchloride which can be configured in one or more filter pressarrangements.

BACKGROUND

Electrochemical cell technology is designed such that an appliedelectric current induces reactions within a cell, converting availablereactants into desired products. An electrolytic cell, or electrolysiscell, is one preferred method of accomplishing this conversion.Electrolysis cells require the conduction of electricity, typicallydirect current, from an external source to a polarized electrode. Theyfurther require conduction away from an electrode of the oppositepolarity, either external to or within the electrochemical cell, togenerate products.

One desirable configuration of an electrochemical cell is that of thefilter press-type electrolyser. Filter press electrolyserelectrochemical cells require: mechanical frames with sufficientrigidity, the ability to be connected to (and removed from) an externalcurrent source, a “current carrier” to provide a current flow path forelectricity to be conducted to the electroactive area, a circulationchamber to provide space for gaseous product generation at theelectroactive area, passageways that allow the input and output ofreactants and products, and finally a capability to form an externalseal that prevents fluids leaking from the interior of the cell to theexternal atmosphere.

Filter press electrolyser electrochemical cells generally come in threeconfigurations, driven by the design of their sub-components: a bipolarcell design, a unipolar cell design, or a monopolar cell design.

Monopolar Cell Design

A “monopolar” cell design or configuration refers to an electrochemicaldevice based upon a current carrying configuration as shown by theexemplary positive half-cell in FIG. 1B. This monopolar configurationcomprises a current carrying structure, and further provides anelectroactive structure of a singular polarity (either anodic orcathodic) on one side of the current carrying structure. As a result, aregion of one polarity is provided on the side of the current carryingstructure that possesses the electroactive structure. Current isprovided into the configuration by a power source and flows in acrossthe current carrier and to the electroactive structure. Typically, thecurrent flows in a parallel direction to the electroactive structure.The half-cell in FIG. 1B creates the base current carrying unit for amonopolar electrochemical filter press device constructed of positiveand negative (anodic and cathodic) half-cell pairs. All monopolar basecurrent carrying units are configured electrically in parallel within asingle filter press arrangement, such that one electrochemical cell isformed within a single filter press stack.

Bipolar Cell Design

The phrase “bipolar configuration” or “bipolar cell configuration”refers to an electrochemical device based upon a current carryingconfiguration as shown in FIG. 1C. This bipolar configuration comprisesa bipolar wall, defining electroactive areas of opposite polarity onopposing sides of the current carrying structure. Regions of oppositepolarity are provided on the opposing sides of the bipolar wall. Currentis provided into the configuration by a power source and flows throughthe bipolar wall orthogonally, creating the base current carrying unitfor a bipolar electrochemical filter press device. Multipleelectrochemical cells within a bipolar filter press are electricallyconnected in series, with each individual current carrier typicallycomprising one anodic and one cathodic side connected by a conductivebipolar wall. The current path in bipolar cells between electroactivestructures of different polarities is typically shorter than theequivalent current path in traditional monopolar designs, and unipolardesigns as described later.

In bipolar cells, the current must only travel through one bipolar wallto reach an electroactive structure of the opposing polarity, whereas intraditional unipolar and monopolar cells additional components arerequired to connect current to opposite polarity electroactivestructures. A shorter current path generally creates lower resistanceparameters within the conductive surfaces of a singular cell. This hastraditionally led to higher voltage losses due to higher electronicresistance voltage loss, and thus lower efficiency, for unipolar andmonopolar cells as compared to bipolar cells for similar currentdensities and similar electroactive structures.

Historically, the contribution of electronic resistance to cell voltagelosses in traditional unipolar and monopolar designs presented thegreatest barrier to the continued commercialization of thesetechnologies. When choosing which direction to take electrolysistechnologies in recent decades, leaders in the electrolysis fieldfocused heavily on the advancement of “zero-gap” bipolar cell designs asthey reduced the contribution of electronic resistance to cell voltagelosses and consequently, for similar current densities and similarelectroactive structures, improved plant energy efficiency. Zero-gapdesigns also allowed bipolar cells to utilize higher current densities.The focus on zero-gap bipolar technology lead to an industrialpreference for bipolar technology as a whole over monopolar and unipolartechnology. However, the utilization of higher current densities doesnot in itself lead to improved efficiency or improved plant economics.Unipolar and monopolar technologies present many complementaryadvantages in these areas, which will be discussed further.

Unipolar Cell Design

A unipolar cell design or configuration refers to an electrochemicaldevice based upon a current carrying configuration as shown by theexemplary positive half-cell in FIG. 1A. This unipolar configurationcomprises a current carrying structure that provides multipleelectroactive structures of the same polarity (either anodic orcathodic) on opposing sides of the current carrying structure. As aresult, regions of the same universal polarity are provided on theopposing sides of the current carrying structure. Current is thenprovided by a power source and flows in across the current carrier andto the electroactive structures. Typically, the current flows in aparallel direction to the electroactive structures. The half-cell inFIG. 1A creates the base current carrying unit for a unipolarelectrochemical filter press device constructed of positive and negative(anodic and cathodic) half-cell pairs. Like the previously describedmonopolar base current carrying unit, all unipolar base current carryingunits are configured electrically in parallel within a single filterpress arrangement, such that one electrochemical cell is formed within asingle filter press stack. Unipolar designs are distinguished frommonopolar designs by the presence and positioning of their electroactivearea(s) among other things.

Historically, only “tank type” unipolar cells have had current carrierscomprising a single chamber bordered by two electroactive structures ofthe same polarity, enabling a single channel for electrochemicalreactants and products to flow between the electroactive structures. Anearly tank type unipolar electrolyser is described in U.S. Pat. No.1,597,552A Electrolytic Cell, Alexander T. Stuart, 1923. Tank typeunipolar designs do not require a frame as part of a single unipolarcurrent carrying electrode. Rather, unipolar electrodes are connectedelectrically in parallel and mounted as a single structure within atank. A major advancement in tank type unipolar electrode design asdescribed in U.S. Pat. No. 4,482,448A Electrode Structure forElectrolyser Cells, Bowen et al, 1981 introduced the world to the firstlarge scale hydrogen production, which was configured to allow largetotal surfaces areas and currents of 120,000 amperes per cell, fromnon-fossil energy. However, despite the advancements that enabled theindustrial scaling of this technology, these tank type unipolar cellsrequired separate tanks, cover plates, penetrations for electrochemicalconnections, and the use of additional parts to form a suitablepassageway for electrochemical reactants and products to pass throughthe electrochemically active regions. “Tank type” configurations ingeneral were replaced by “filter press type” configurations because ofthe large quantity of their parts, the complexity of their assembly, andthe difficulty in changing the surface area per cell.

The additional components required by unipolar tank type cells yielded alonger current path between electroactive structures of opposingpolarities than bipolar designs, and consequently higher resistancewithin the conductive pathways required for a single cell. A doubleplated monopolar filter press frame design was created which reducedpart count and current path lengths as compared to unipolar tank typecells, while affording many of the commercial benefits of unipolartechnology in U.S. Pat. No. 6,080,290A Mono-polar electrochemical systemwith a double electrode plate, A.T.B. Stuart et al., 1997.

However, the monopolar double plate design of U.S. Pat. No. 6,080,290Apossessed features that were challenging to manufacture. In addition,the monopolar plate design of U.S. Pat. No. 6,080,290A necessitated thatnon-conductive chamber-creating sealing gasket(s) be positioned betweenmonopolar plates of the same polarity, which were positioned back toback, with the chamber-creating sealing gaskets between them. Further,should a thick electroactive structure have been employed to enableincreases in this design's lateral width (thus increasing its surfacearea in the direction current travels), even further use of thechamber-creating “spacer gaskets” would have been necessitated. Overall,the requirement to provide such spacer gaskets with each monopolar plateaddition imposed mechanical and structural limitations to the filterpress design, specifically: limited ability to seal a large quantity ofmonopolar plates within a single filter press, limited ability tooperate at elevated internal pressure, and limits on the methods tosupport the separator within the filter press. Further, providingadditional gaskets required more parts be manufactured, slowedconstruction of the cell, and imposed restrictions on the compressionmethods used for the filter press stack.

A unipolar filter press cell stack is described in U.S. Pat. No.4,490,231 Electrolytic cell of the filter press type, Boulton, 1982,however its design imposes similar advantages and limitations to themonopolar filter press design of U.S. Pat. No. 6,080,290A. Like themonopolar filter press design of U.S. Pat. No. 6,080,290A thelimitations of U.S. Pat. No. 4,490,231 include: the need to useadditional spacer gaskets to form a chamber, limited ability to seal alarge quantity of plates within a single filter press (because of thesoft materials being used to form a chamber), limited ability to operateat elevated internal pressure, limits on the method used to support theseparator in the filter press, and finally limitations on the ability toexpand electroactive structure length in the direction current travels(to increase electroactive surface area for the purpose of conductinggreater electricity over longer distances).

To elaborate on the latter limitation, for the filter press of U.S. Pat.No. 4,490,231 to expand the electroactive structure in the directioncurrent travels while maintaining the same specified resistive loss, itwould require a thicker current carrying structure, as its main currentcarrying structure is provided from the same part as its electroactivestructure. This is disadvantageous because: forming the electroactivestructure of U.S. Pat. No. 4,490,231 involves cutting and bending (whichwould become increasingly expensive as the current carrier grewthicker), applying extra electrocatalysis to the expanded currentcarrier would increase costs, and finally the thickness of the requiredspacer-gasket becomes larger, which exacerbates the associatedlimitations listed above. Additionally, the short and wide rectangularshape of the unipolar filter press of U.S. Pat. No. 4,490,231 does notminimize the potential footprint of the electrochemical device, as thetall and narrow monopolar plate embodiment does in U.S. Pat. No.6,080,290A.

In summary, the monopolar filter press U.S. Pat. No. 6,080,290Aovercomes some of the disadvantages of tank type unipolar cells, byproviding shorter current paths which allow for lower ohmic resistancelosses. In addition, the monopolar filter press has a lower part countand much lower construction costs than the unipolar tank type cell.Furthermore, the unipolar filter press of U.S. Pat. No. 4,490,231 doesnot have a generally tall and narrow geometry, and it combines itscurrent carrier and electroactive structure in one part, thus limitingthe design choices available for its thickness and manufacturing method.

It should be noted that both the filter press electrolysers of U.S. Pat.Nos. 6,080,290A and 4,490,231 orient their electroactive structures suchthat they are in parallel with the direction of current flow.Consequently, these designs allow for multiple electrode structures tobe placed within the same electrochemical cell. In view of this, theindividual electrochemical cell can expand its surface area by extendingthe filter press longitudinally to its physical limit. This leads tovery high current being able to flow through a monopolar or unipolarcell.

In contrast, bipolar filter press arrangements incorporate a number ofcells longitudinally within one filter press stack. Further, in abipolar filter press, the electrode structure of a bipolar cell remainsperpendicular to the direction of current flow. With this construction,there are practical limits on the surface area of a single bipolar cell.Practical surface area limits are imposed as the electrolytic reactantsand products need to distribute throughout the bipolar electrodestructure, while balancing limits in practical manufacturing techniquesas well as transportation of a filter press from its point offabrication to the operating site. Limits on practical surface arealeads to lower limits on the amount of current that can flow through abipolar filter press, as compared with a monopolar or unipolar filterpress. For example, in water electrolysis processes over the past 40years, current has ranged typically up to 10,000 amperes in a bipolarfilter press as compared with 120,000 amperes in a unipolar cell.Furthermore, multiple bipolar filter presses are not practicallyemployed in parallel with each other to increase this amperage, due tothe differences in resistivity between each filter press. Therefore, forthe purpose of creating large surface area electrolysis cells, bipolarcells are not practical.

By the year 2020, the cost of implementing renewable forms ofelectricity production through technologies such as wind turbines andphotovoltaics has dramatically fallen from historical levels. Ratherthan being one of the most expensive sources of electricity, as theywere in the 1970's and 1980's, photovoltaics and wind turbines are nowsome of the world's lowest-cost electricity sources, and are indigenousto every country across the globe. Integrating these renewable energytechnologies with large scale water electrolysis cells can producerenewably made hydrogen at historically low costs. These costs in manycases can be lower than the cost of hydrogen produced from fossil fuels,and have the potential to enable the long-term replacement of fossilenergy with renewable energy.

However, in order to replace fossil-based hydrogen with renewable-basedhydrogen, water electrolysers are required on the order of 100 to 1000times larger than what has generally been used in industry over the past20 years. For example, one large-scale ammonia production facility,which would source its hydrogen from renewable energy sources and waterelectrolysis units, would need approximately 2,000 MW of power.Therefore, the water electrolysers are required to have, among otherfeatures, very high individual cell currents (for example 50,000 to500,000 amperes) in order to minimize the quantity of small-scale powerconditioning systems required to provide DC current to theelectrolysers.

Looking to other electrolysis fields, high current electrolysistechnology with a minimum number of high current power conditioningsystems represents the state of the art for large power electrochemicalprocesses, such as electrolysis for chlorine production and aluminiumproduction. Thus, to advance renewable hydrogen systems at scale,unipolar electrolysers with maximized surface areas that consequentlyallow maximized electrical currents are highly desired.

It would be particularly desirable for a unipolar filter presselectrolyser design to be configured in a tall rectangular shape,wherein (as compared to both U.S. Pat. Nos. 4,490,231 and 6,080,290A)the part count is reduced, conductivity is increased, the number ofchamber-forming gaskets is reduced, the ability to operate underelevated pressures is provided, the ability to expand the electroactivestructures in the direction of the current flow is provided, andadditional incremental electrode plates within the filter press can bereadily provided while still successfully sealing the filter press.

SUMMARY

Unipolar filter press electrolysis systems are provided in arrangementsparticularly preferred for large scale electrochemical processes such asalkaline water electrolysis, sodium chlorate electrolysis, andchlor-alkali electrolysis based on favourable geometries of the currentcarrier, circulation chamber and rigid support frame members (CCF's)disclosed herein.

The present disclosure provides an integrally combined electricallyconductive current carrier, circulation chamber, and rigid support framemember for use in a unipolar electrochemical apparatus, comprising:

-   -   a) a one-piece electrically conductive frame and circulation        chamber having spaced apart opposed first and second side arms        with the side arms extending at both ends thereof between first        and second lateral cross members;    -   b) a first generally L-shaped member with two arms with an end        of one arm integrally formed with the second side arm and an end        of the other arm integrally formed with the second lateral cross        member to give a third channel defining aperture and a first        adjacent channel defining aperture in the rigid support frame        member;    -   c) a second generally L-shaped member with two arms with an end        of one arm integrally formed with the first side arm and an end        of the other arm integrally formed with the first lateral cross        member to give a fourth channel defining aperture and a second        adjacent channel defining aperture in the rigid support frame        member;    -   d) one of the side arms configured to be connected to a power        source; and    -   e) the rigid support frame member having an integrally provided        circulation chamber for the circulation of electrolyte,        products, and reactants, and wherein the circulation chamber is        formed by        -   i) a depth dimension provided between opposed surface planes            of said first and second side arms which is a thickness of            the rigid support frame member, and        -   ii) the inner dimension between the first and second side            arms, and        -   iii) the inner dimension between the L-shaped arm sections            parallel to the lateral cross members.

The rigid support member may be a first rigid support frame member, andfurther comprising at least a second rigid support frame memberintegrally connected to and formed with the first rigid support framemember along a central frame member with the second rigid support framemember being coplanar with the first rigid support frame member. Thesecond rigid support frame member is a mirror image of the first rigidsupport frame member along an axis defined by the integral connectionalong the central frame member between the first and second rigidsupport frame members to give a mirror image of the first and secondlateral cross members and a mirror image of the generally L-shapedmembers to give two generally L-shaped members at upper and lower endsof the double current carrier, circulation chamber, and rigid supportframe member to define eight apertures respectively in the doublecurrent carrier. The central frame member is configured to provide powerbetween the outer first and second side arms and the first and secondlateral cross members.

The first generally L-shaped member may further comprise one or moreadditional arms positioned such that the third channel defining apertureis divided to provide one or more additional channel defining apertures,the arm adjacent-most to the first channel defining aperture furthercomprising at least one through-point allowing liquids and/or residualgases to flow from the first channel defining aperture intoadjacent-most channel defining aperture.

The present disclosure also provides a unipolar filter presselectrolyser apparatus, comprising:

-   -   a) a plurality of the integrally combined single current        carrier, circulation chamber, and rigid support frame members        stacked side by side each other to form a stack and being        aligned such that said channel defining apertures in each        support frame member align with corresponding channel defining        apertures and masking frames placed in alternating channel        defining apertures in all other support frame members, the        plurality of support frame members including two end support        frame members each one located at opposed ends of the stack;    -   b) the circulation chamber in a given rigid support frame member        being separated from the circulation chambers in rigid support        frame members on each side of the given rigid support frame        members by a separator such that said circulation chambers in        each of the plurality of rigid support frame members are        separated from each other;    -   c) the plurality of rigid support frame members being separated        from each other by sealing and electrically insulating gaskets        having the same general shape and dimensions of said rigid        support frame members;    -   d) two end clamping plates each one located on an outside of the        two end rigid support frame members for clamping the unipolar        filter press electrolyser apparatus together, each of the end        clamping plates including two ports, one for feeding liquids        and/or gases into the stack and the other for extracting liquids        and/or gases from the stack;    -   e) a gasket located between each end clamping plate and its        associated end rigid support frame member for insulating each        end clamping plate from its associated end rigid support frame        member, each of the gaskets including two apertures located        therein to align with the two ports in each end clamping plate;        and    -   f) wherein when the unipolar filter press electrolyser apparatus        is assembled, the channel defining apertures in each of the        rigid support frame members and said gaskets align with each        other to form flow passageways through said stack with two of        the flow passageways aligned with the two ports in each end        clamping plate.

The present disclosure provides a unipolar filter press electrolyserapparatus, comprising:

-   -   a) a plurality of integrally combined double current carrier,        circulation chamber, and rigid support frame members stacked        side by side each other to form a double stack and being aligned        such that said channel defining apertures in each double rigid        support frame member align with corresponding channel defining        apertures, and masking frames placed in alternating channel        defining apertures, in all other support frame members, the        plurality of double rigid support frame members including four        individual rigid end support frame members each located at        opposed ends of the stack;    -   b) the circulation chambers in a given double rigid support        frame member being separated from the circulation chambers in        double rigid support frame members on each side of the given        double rigid support frame member respectively by separators        such that the circulation chambers in each of the plurality of        double rigid support frame members are separated from each        other;    -   c) the plurality of double rigid support frame members being        separated from each other by sealing and electrically insulating        gaskets having the same general shape and dimensions of the        individual halves of the double rigid support frame members;    -   d) four end clamping plates each one located on an outside of        the four end rigid support frame members for clamping the        unipolar filter press electrolyser apparatus together, each of        the end clamping plates including two ports, one for feeding        liquids and/or gases into the stack and the other for extracting        liquids and/or gases from the stack;    -   e) a gasket located between each end clamping plate and its        associated end rigid support frame member for insulating each        end clamping plate from its associated end rigid support frame        member, each of the gaskets including two apertures located        therein to align with the two ports in each end clamping plate;        and    -   f) wherein when the unipolar filter press electrolyser apparatus        is assembled, the channel defining apertures in each of the        double rigid support frame members and the gaskets align with        each other to form flow passageways through the double stack        with eight flow passageways aligned with the two ports in each        of the four end clamping plates.

The present disclosure also provides a unipolar filter presselectrolyser apparatus, comprising:

-   -   a) a plurality of integrally combined current carrier,        circulation chamber, and rigid support frame members stacked        side by side each other to form a stack and being aligned such        that the channel defining apertures in each support frame member        align with corresponding channel defining apertures, and masking        frames placed in alternating channel defining apertures, in all        other support frame members, the plurality of support frame        members including two end support frame members each one located        at opposed ends of the stack;    -   b) the circulation chamber in a given rigid support frame member        being separated from the circulation chambers in rigid support        frame members on each side of the given rigid support frame        members by a separator such that the circulation chambers in        each of the plurality of rigid support frame members are        separated from each other;    -   c) the plurality of rigid support frame members being separated        from each other by sealing and electrically insulating gaskets        having the same general shape and dimensions of the rigid        support frame members;    -   d) two end clamping plates each one located on an outside of the        two end rigid support frame members for clamping the unipolar        filter press electrolyser apparatus together, each of the end        clamping plates including a number of ports proportional to the        number of channel defining apertures in each adjacent end rigid        support frame member for feeding and extracting liquids and/or        gases into and from the stack of a given polarity;    -   e) a gasket located between each end clamping plate and its        associated end rigid support frame member for insulating each        end clamping plate from its associated end rigid support frame        member, each of the gaskets including a number of apertures        located therein to align with the number of ports in each end        clamping plate; and    -   f) wherein when said unipolar filter press electrolyser        apparatus is assembled, the channel defining apertures in each        of said rigid support frame members and the gaskets align with        each other to form a number flow passageways proportional to the        number of channel defining apertures through the stack with the        number of flow passageways aligned with the number of ports in        each end clamping plate.

The present disclosure further provides a unipolar filter presselectrolyser apparatus, comprising:

-   -   a) a plurality of integrally combined double current carrier,        circulation chamber, and rigid support frame members stacked        side by side each other to form a double stack and being aligned        such that said channel defining apertures in each support frame        member align with corresponding channel defining apertures, and        masking frames placed in alternating channel defining apertures,        in all other support frame members, the plurality of support        frame members including four individual end support frame        members each one located at opposed ends of the stack;    -   b) the circulation chambers in a given double rigid support        frame member being separated from the circulation chambers in        double rigid support frame members on each side of the given        double rigid support frame member respectively by separators        such that the circulation chambers in each of the plurality of        double rigid support frame members are separated from each        other;    -   c) the plurality of double rigid support frame members being        separated from each other by sealing and electrically insulating        gaskets having the same general shape and dimensions of the        individual halves of the double rigid support frame members;    -   d) four end clamping plates each one located on an outside of        the four end rigid support frame members for clamping the        unipolar filter press electrolyser apparatus together, each of        the end clamping plates including a number of ports proportional        to the number of channel defining apertures in each adjacent end        rigid support frame member for feeding and extracting liquids        and/or gases into and from the stack of a given polarity;    -   e) a gasket located between each end clamping plate and its        associated end rigid support frame member for insulating each        end clamping plate from its associated end rigid support frame        member, each of the gaskets including a number of apertures        located therein to align with the number of ports in each end        clamping plate; and    -   f) wherein when the unipolar filter press electrolyser apparatus        is assembled, the channel defining apertures in each of the        double rigid support frame members and the gaskets align with        each other to form flow passageways through the double stack        with said number of flow passageways aligned with the number of        ports for gas/liquid product feed/discharge of a given polarity        in each of the four end clamping plates.

The present disclosure further provides a unipolar filter pressmulti-cell block apparatus, expanded laterally and electrically inseries by means of overlapping halves of the double rigid support framemembers therein, such that one double rigid support frame member isshared between two laterally adjacent unipolar electrochemical cells,such that current passes in series between said laterally adjacentunipolar electrochemical cells, such that the multi-cell block in totalcomprises 3 or more unipolar electrochemical cells connected laterallyin series by means of said shared double rigid support frame members,each unipolar cell being further capable of expanding longitudinallyelectrically in parallel to suit the surface area per cell required forthe multi-cell block's application, and such that said sealing gasketsmasking frames and clamping plates are proportionally scaled to therequirements of the multi-cell block such that the system may be sealedand clamped, and gases and liquids may be fed and discharged therefrom.

A further understanding of the functional and advantageous aspects ofthe present disclosure can be realized by reference to the followingdetailed description and drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Embodiments will now be described, by way of example only, withreference to the accompanying drawings, in which:

FIG. 1A shows the top down view of a base current carrying half-cellunit of a unipolar electrochemical filter press device, comprisingelectroactive structures of the same polarity on opposing sides of thecurrent carrier configured electrically in parallel;

FIG. 1B shows the top down view of a base current carrying half-cellunit of a monopolar electrochemical filter press device, comprising oneelectroactive structure of a single polarity on one side of the currentcarrier configured electrically in parallel;

FIG. 1C shows the top down view of a base current carrying unit of abipolar electrochemical filter press device, comprising a bipolar walldefining electroactive areas of opposite polarity configuredelectrically in series;

FIG. 2 shows a disassembled isometric view of a unipolar filter presselectrochemical device based upon the part of FIG. 3A;

FIG. 3A shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part accordingto the present disclosure for use in unipolar filter press typeelectrochemical devices;

FIG. 3B shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame according to the presentdisclosure for use in unipolar filter press type electrochemical devicesadditionally comprising exemplary electroactive structures on opposingsides of the part;

FIG. 3C shows an isometric view of simplified sketches of a range ofelectroactive structures for a unitary current carrier, productcirculation chamber, and structural frame;

FIG. 3D shows a disassembled isometric view of various insertablegasket-support components further comprising flow controlling channels;

FIG. 3E shows an isometric view of exemplary embodiments of a pair ofunitary current carriers, product circulation chambers, and structuralframes according to the present disclosure for use in unipolar filterpress electrochemical devices wherein one is distinctly an anode and oneis distinctly a cathode;

FIG. 3F shows a disassembled isometric view of various alternativeembodiments of gasket-support components, said alternativegasket-support components being provided integrally as part of theunitary current carrier, product circulation chamber, and structuralframe;

FIG. 3G shows an isometric view of exemplary alternative embodiments ofunitary current carriers, product circulation chambers, and structuralframes according to the present disclosure for use in unipolar filterpress electrochemical devices wherein alternative embodiments ofgasket-support components are provided integrally as part of the unitarycurrent carrier, product circulation chamber, and structural frame;

FIG. 4A shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part accordingto the present disclosure for use in unipolar filter press typeelectrochemical devices with additional perforated rungs to improvecurrent carrying capabilities and part performance under pressurization;

FIG. 4B shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame of FIG. 4A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 5A shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part accordingto the present disclosure for use in unipolar filter press typeelectrochemical devices, with diagonally oriented spears provided fromthe same unitary part to concentrate current carrying capabilities andproduct generation near the electrical input source, consequentlyallocating the remaining space for generated products to exit thecirculation chamber;

FIG. 5B shows an isometric view of the unitary current carrier, productcirculation chamber, and structural frame of FIG. 5A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 5C shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part accordingto the present disclosure for use in unipolar filter press typeelectrochemical devices, further comprising an alternative embodiment ofdiagonally oriented spears provided from the same unitary part, extendedframe members to enable improved heat transfer, and additional materialcut-outs provided within the part to reduce weight among other benefits;

FIG. 6A shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part accordingto the present disclosure for use in unipolar filter press typeelectrochemical devices with additional rungs provided from the sameunitary part to improve current carrying capabilities and partperformance under pressurization, further provided with intra-rungchannels to create product exit pathways and provide designated sitesfor intra-rung electroactive structure attachment;

FIG. 6B shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame of FIG. 6A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 7 shows a disassembled isometric view of a unipolar filter presselectrochemical device based upon a combination of the parts of FIG. 8Aand FIG. 3A;

FIG. 8A shows an isometric view of a unitary part for use in unipolarfilter press type electrochemical devices according to the presentdisclosure wherein a current carrier and structural frame are shared bytwo distinct product circulation chambers provided in the same unitarypart;

FIG. 8B shows an isometric view of the unitary part for use in unipolarfilter press type electrochemical devices of FIG. 8A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 9A shows an isometric view of a unitary part for use in unipolarfilter press type electrochemical devices according to the presentdisclosure wherein a current carrier and structural frame are shared bytwo distinct product circulation chambers provided in the same unitarypart with additional perforated rungs to improve current carryingcapabilities and part performance under pressurization;

FIG. 9B shows an isometric view of the unitary part for use in unipolarfilter press type electrochemical devices of FIG. 9A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 10A shows an isometric view of a unitary part for use in unipolarfilter press type electrochemical devices according to the presentdisclosure wherein a current carrier and structural frame are shared bytwo distinct product circulation chambers provided in the same unitarypart with diagonally oriented spears provided from the same unitary partto concentrate current carrying capabilities and product generation nearthe electrical input source and consequently allocate the remainingspace for generated products to exit the circulation chambers;

FIG. 10B shows an isometric view of the unitary part for use in unipolarfilter press type electrochemical devices of FIG. 10A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 10C shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part accordingto the present disclosure for use in unipolar filter press typeelectrochemical devices, further comprising an alternative embodiment ofdiagonally oriented spears provided from the same unitary part, extendedframe members to enable improved heat transfer, and additional materialcut-outs provided within the part to reduce weight among other benefits;

FIG. 11A shows an isometric view of a unitary part for use in unipolarfilter press type electrochemical devices according to the presentdisclosure wherein a current carrier and structural frame are shared bytwo distinct product circulation chambers provided in the same unitarypart with additional rungs provided from the same unitary part toimprove current carrying capabilities and frame performance underpressurization, further provided with intra-rung channels to createproduct exit pathways and provide designated sites for intra-rungelectroactive structure attachment;

FIG. 11B shows an isometric view of the unitary part for use in unipolarfilter press type electrochemical devices of FIG. 11A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 12 shows a disassembled isometric view of a unipolar filter presselectrochemical device based upon the unitary part of FIG. 13A;

FIG. 13A shows an isometric view of a unitary current carrier, productcirculation chamber, and structural frame provided in one part for usein unipolar filter press type electrochemical devices according to thepresent disclosure, further provided with a non-limiting number ofadditional passageways for the flow of reactants and products into andout of the part, as best suited to the engineering requirements of theunipolar electrochemical application;

FIG. 13B shows an isometric view of the unitary current carrier, productcirculation chamber, and structural frame of FIG. 13A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 14 shows a disassembled isometric view of a unipolar filter presselectrochemical device based upon the combination of the unipolar partsof FIG. 15A and FIG. 13A;

FIG. 15A shows an isometric view of a unitary part for use in unipolarfilter press type electrochemical devices according to the presentdisclosure, wherein a current carrier and structural frame are shared bytwo distinct product circulation chambers provided in the same unitarypart, with a non-limiting number of additional passageways for the flowof reactants and products into and out of the part, to best suit theengineering requirements of the unipolar electrochemical application;

FIG. 15B shows an isometric view of the unitary part for use in unipolarfilter press type electrochemical devices of FIG. 15A additionallycomprising exemplary electroactive structures on opposing sides of thepart;

FIG. 16A shows a simplified top-down view of the innermost components ofthe unipolar filter press electrochemical device of FIG. 2 (theinnermost components of FIG. 7 would also behave equivalently from thisview) and the consequent path of current upon said innermost componentsand their electroactive structures, illustrating in particular thecurrent travelling parallel to the product-generating electroactivestructures;

FIG. 16B shows a simplified top-down view of the innermost components ofthe unipolar filter press electrochemical device shown in FIG. 7 (theinnermost components of FIG. 14 would also behave equivalently from thisview) and the consequent path of current upon said innermost componentsand their electroactive structures, illustrating in particular thecurrent travelling parallel to the product-generating electroactivestructures;

FIG. 16C shows a simplified top-down view of the innermost components ofan embodiment of a multi-unipolar-cell filter press electrolyser blockaccording to the present disclosure, based on a combination of partsFIG. 8A and FIG. 3A (or equivalently FIG. 13A and FIG. 15A) showing inparticular that additional replicates of said components may be added tothe device to provide more than two filter press stacks in a singleblock assembly; thus scaling the device and increasing the product at alow incremental cost.

DETAILED DESCRIPTION

Various embodiments and aspects of the disclosure will be described withreference to details discussed below. The following description anddrawings are illustrative of the disclosure and are not to be construedas limiting the disclosure. The figures are not to scale. Numerousspecific details are described to provide a thorough understanding ofvarious embodiments of the present disclosure. However, in certaininstances, well-known or conventional details are not described in orderto provide a concise discussion of embodiments of the presentdisclosure.

As used herein, the terms, “comprises” and “comprising” are to beconstrued as being inclusive and open ended, and not exclusive.Specifically, when used in the specification and claims, the terms“comprises” and “comprising” and variations thereof mean the specifiedfeatures, steps or components are included. These terms are not to beinterpreted to exclude the presence of other features, steps orcomponents.

As used herein, the term “exemplary” means “serving as an example,instance, or illustration,” and should not be construed as preferred oradvantageous over other configurations disclosed herein.

As used herein, the terms “about” and “approximately” are meant to covervariations that may exist in the upper and lower limits of the ranges ofvalues, such as variations in properties, parameters, and dimensions. Inone non-limiting example, the terms “about” and “approximately” meanplus or minus 10 percent or less.

As used herein, the terms “generally” and “essentially” are meant torefer to the general overall physical and geometric appearance of afeature and should not be construed as preferred or advantageous overother configurations disclosed herein.

As used herein, the terms “stack” or “filter press stack” or “filterpress” is meant to refer to, but not exclusively, the generalconfiguration of the assembled unipolar electrochemical device in afilter press configuration.

As used herein, the phrase “electroactive structures” or “electroactivesurfaces” refers to conductive screens, expanded metal and perforatedplates, essentially flat and thin in shape which may or may not becoated with a catalyst, depending on the electroactive material andelectrochemical reaction it is intended for in the particular stack.

As used herein, the phrase “sealing profile” refers to the profile alongthe longitudinal axis of a filter press electrolyser, defined by theouter boundaries of all components within said filter press electrolyserwhich serve a function of forming an external seal that prevents fluidsleaking from the interior of the filter press to the externalatmosphere, said components including but not limited to gasketing andmasking components.

As used herein, the phrase “generally L-shaped” includes shapes that arenot strictly “L-shaped.” For example, a “generally L-shaped” member maybe formed as a passageway defining structure, such that adjacentpassageways are formed complementary to each other in a filter pressstack.

PARTS LIST

-   -   FIG. 1A: Unipolar Current Carrying Configuration    -   FIG. 1B: Monopolar Current Carrying Configuration    -   FIG. 1C: Bipolar Current Carrying Configuration    -   210—top-down view and cross section of the electroactive region        of a basic unipolar current carrying configuration with        electroactive structures attached;    -   212—top-down view and cross section of the current carrier;    -   214—power input into the cell;    -   102—electrically conductive mesh, perforated or slotted sheet,        expanded sheet, screens, woven mesh or similar appropriate        planar configuration thereof forming the anodic electroactive        structure and designated as an anodic mesh with the positive        sign in FIG. 2 ;    -   216—Current entering from the side of the configuration, and        travelling in parallel with the surface of electroactive        structure 102;    -   218—top-down view and cross section of the electroactive region        of a basic monopolar current carrying configuration with an        electroactive structure attached;    -   220—top-down view and cross section of the electroactive region        of a basic bipolar current carrying configuration;    -   222—top-down view and cross section of a conductive bipolar        wall;    -   224—Current entering orthogonally to the conductive bipolar wall        and traveling orthogonally through it;    -   226—positive electroactive region;    -   228—negative electroactive region;    -   FIG. 2 : Isometric Full Assembly of Single CCF Parts    -   FIG. 3A: Single CCF    -   FIG. 3B: Single CCF with Electroactive Structures    -   FIG. 3C: Various Electroactive Structures    -   FIG. 3D: Gasket support pieces    -   FIG. 3E: Anode and Cathode Variations    -   FIG. 3F: Alternative Integrally Provided Gasket Support Pieces    -   FIG. 3G: Alternative Integrally Provided Gasket Support Pieces        in CCFs    -   10—the assembled stack    -   12—first of two end clamping plates (also referred to as an end        plate);    -   14—first full faced gasket with two pathways defining apertures        110 and 111 connecting between the first monopolar CCF 21 and        first clamping plate 12 and second full faced gasket with two        pathways defining apertures 94 and 109 connecting with the        second monopolar CCF 21 and second clamping plate 34;    -   20—electrically conductive current carrier circulation chamber        and frame (double faced CCF) of positive polarity;    -   21—electrically conductive current carrier circulation chamber        and frame (single faced CCF) of negative polarity;    -   22, 24—masking frames;    -   26—electrically conductive mesh, perforated or slotted sheet,        expanded sheet, screens, woven mesh or similar appropriate        planar configuration thereof forming the cathodic electroactive        structure with the − sign in FIG. 2 ;    -   28—separator;    -   30—sealing and electrically insulating gasket between CCF's of        different polarities;    -   34—second of two end clamping plates (also referred to as an end        plate);    -   40—non-limiting example of a planar electroactive structure        material comprising a continuous sheet of circular perforations;    -   41—non-limiting example of a planar electroactive structure,        comprising a continuous perforated sheet of continuous slots;    -   42—non-limiting example of a planar electroactive structure,        comprising a continuous slotted sheet;    -   43—non-limiting example of a planar electroactive structure,        comprising a continuous sheet of hexagonal perforations;    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   45—non-limiting example of a planar electroactive structure,        comprising a continuous woven mesh;    -   48—first tubular port for feeding or extracting products to/from        end plate 34;    -   49—first tubular port for feeding or extracting products to/from        end plate 12;    -   50—electrically conductive metal frame circulation chamber and        current carrier, generic for CCF's 20 and 21;    -   50A—exemplary cathodic embodiment of conductive metal frame        circulation chamber and current carrier 50;    -   50B—exemplary anodic embodiment of conductive metal frame and        current carrier electrically conductive metal frame and current        carrier, generic for CCF's 20 and 21;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   52—first channel defining aperture in frame 20;    -   53—short side section of frame 50, 68, 74, 85;    -   54—third channel defining aperture in frame 20;    -   55—opposing long side section of frames 50, 68, 74, 85;    -   56—non-limiting channel defining gasket support pieces; with        channels provided therein to control product and reactant        passage into and out of apertures through the provision of        channels of a defined size and shape;    -   56A—non-limiting friction-fit insertion points for gasket        support pieces 56 to be received    -   56B—channel defining gasket support pieces provided integrally        as part of the CCF embodiment of 50 to control product and        reactant passage into and out of a CCF through the provision of        channels;    -   56C—channel defining gasket support pieces provided integrally        as part of the CCF embodiment of 50 to control product and        reactant passage into and out of a CCF through the provision of        an aperture;    -   56D—channel defining gasket support pieces provided integrally        as part of the CCF embodiment of 50 to control product and        reactant passage into and out of a CCF by means of one or more        supportive T-shaped gasket support pieces;    -   56E, 56F—channel defining gasket support pieces provided        integrally as part of the CCF embodiment of 50 to control        product and reactant passage into and out of a CCF by means of        one or more negative T shapes embedded in the integrally        provided gasket support;    -   57—second tubular port for feeding or extracting products        to/from end plate 34;    -   59—tubular port for feeding or extracting products to/from plate        34;    -   63—first delimiting conducting strut between circulation chamber        103 and channel defining apertures 52 and 54;    -   64—electrically conductive tab for connection to a source of        power;    -   64A—serrations provided in the electrically conductive tab 64    -   66—first notch;    -   67—second notch;    -   78—fourth channel defining aperture in frame 50;    -   79—cut-outs provided in a CCF;    -   80—second channel defining aperture in frame 50 shown by 80 in        frame 20 but by 100 in frame 21 of FIG. 2 ;    -   90—third channel defining apertures in gasket 30;    -   94—first channel defining aperture in second gasket 14    -   98—first channel defining aperture in frame 21;    -   99—third channel defining aperture in frame 21;    -   100—fourth channel defining aperture in frame 21;    -   101—second channel defining aperture in frame 21;    -   102—electrically conductive mesh, perforated or slotted sheet,        expanded sheet, screens, woven mesh or similar appropriate        planar configuration thereof forming the anodic electroactive        structure and designated as an anodic mesh with the + sign in        FIG. 2 ;    -   103—circulation chamber, provided by the CCF depth 103A;    -   103A—depth dimension of circulation chamber 103    -   104—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 78;    -   106—first channel defining aperture in gasket 30;    -   107—second channel defining aperture in gasket 30;    -   108—fourth channel defining aperture in gasket 30;    -   109—second channel defining aperture in second gasket 14;    -   110—first channel defining aperture in first gasket 14;    -   111—second channel defining aperture in first gasket 14;    -   114—strut delimiting the apertures 52 and 54 at first end of        frame 50, 68, 74, 85;    -   115—strut delimiting the apertures 78 and 80 at second end of        frame 50, 68, 74, 85;    -   116—first channel forming embodiment formed through port 48 in        end plate 34, and apertures 94, 98, 106, and 52;    -   117—second channel forming embodiment formed through port 57 in        second clamping plate 34, and apertures 109, 101, 107, and 80;    -   118—third channel forming embodiment formed through port 49 in        end plate 12, and apertures 110, 99, 90, 54, 90, and 99;    -   119—fourth channel forming embodiment formed through port 59 in        end plate 12, 111, 100, 108, 78, 108 and 100;    -   120—non-limiting example of a gasket support piece with slotted        channels provided therein to control product and reactant        passage into and out of apertures through the provision of        channels of a defined size and shape;    -   121—non-limiting example of a gasket support piece with        wave-like channels provided therein to control product and        reactant passage into and out of apertures through the provision        of channels of a defined size and shape;    -   122—non-limiting example of a gasket support piece wherein        channels are punched, stamped, drill pressed, or inserted by        other mechanical means within the piece to control product and        reactant passage into and out of apertures through the provision        of channels of a defined size and shape;    -   FIG. 4A: Single CCF with Conductive “Dog Bones”    -   FIG. 4B: Single CCF with Conductive “Dog Bones” and        Electroactive Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   53—short side section of frame 50, 68, 74, 85;    -   55—opposing long side section of frames 50, 68, 74, 85;    -   68—Frame of single CCF with dog bones (electrically conductive        metal frame circulation chamber and current carrier, could be        substituted equivalently for CCF's 20 and 21;)    -   66—first notch;    -   67—second notch;    -   69—Big dog bones (removable electrically conductive struts        across circulation chamber 103;)    -   70—holes in the dog bone rungs (portion of strut 69 which is a        channel defining strut section; the channel defining strut        section being punched, stamped, drill pressed, or inserted by        other mechanical means within strut 69;)    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103;    -   114—strut delimiting the apertures 52 and 54 at first end of        frame 50, 68, 74, 85;    -   115—strut delimiting the apertures 78 and 80 at second end of        frame 50, 68, 74, 85;    -   FIG. 5A: Single CCF with Conductive Spears    -   FIG. 5B: Single CCF with Conductive Spears and Electroactive        Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   55—opposing long side section of frames 50, 68, 74, 85;    -   53—short side section of frame 50, 68, 74, 85;    -   66—first notch,    -   67—second notch,    -   74—Frame of single CCF with spears (Electrically conductive        metal frame circulation chamber and current carrier, could be        substituted equivalently for CCF's 20 and 21 in FIG. 2 and FIG.        7 );    -   74A—CCF 74 employing spears 76A;    -   76—“Spears” of single CCF 74 (diagonally oriented        spear-protrusions provided as part of 74, located adjacent to        where power is to be provided in the frame);    -   76A—an alternate embodiment of spears 76;    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103;    -   114—strut delimiting the apertures 52 and 54 at first end of        frame 50, 68, 74, 85;    -   115—strut delimiting the apertures 78 and 80 at second end of        frame 50, 68, 74, 85;    -   FIG. 6A: Single CCF with Conductive Struts    -   FIG. 6B: Single CCF with Conductive Struts and Electroactive        Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   53—short side section of frame 50, 68, 74, 85;    -   58—electrically conductive struts across circulation chamber        103;    -   60—portion of strut 58 which is a channel defining strut        section;    -   62—raised portions of struts 58 used as attachment points for        the electroactive structure;    -   66—first notch;    -   67—second notch;    -   85—electrically conductive metal frame circulation chamber and        current carrier, could be substituted equivalently for CCF's 20        and 21;    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103    -   114—strut delimiting the apertures 52 and 54 at first end of        frame 50, 68, 74, 85;    -   115—strut delimiting the apertures 78 and 80 at second end of        frame 50, 68, 74, 85;    -   FIG. 7 : Isometric Full Assembly of Double and Single CCF Parts    -   310—the assembled stack of combined double and single CCFs;    -   312—first of two end clamping plates (also referred to as an end        plate);    -   316—first channel forming embodiment formed through port 355 in        first end clamping plate 312, and apertures 110, 54, 106, 352;    -   317—second channel forming embodiment formed through port 356 in        first end plate 312 (obscured by first right-hand gasket 14),        111, 78, 107, 380;    -   318—third channel forming embodiment formed through port 351 in        first end plate 334, and apertures 94, 52, 90, 354 of double CCF        350, 90 and 52;    -   319—fourth channel forming embodiment formed through port 353 in        first end clamping plate 334, and apertures 109, 80, 108, 378,        108, 80;    -   320—fifth channel forming embodiment formed through port 348        connecting to second end plate 334, and apertures 94 (not shown        due to cutaway), 54, 90, 356;    -   321—sixth channel forming embodiment formed through port 357 in        second end plate 334, and apertures 109, 78, 108, and 381    -   322—seventh channel forming embodiment formed through port 349        in second end plate 312, and aperture 110, 52, 106, 355 in        double CCF 350, 106, 52;    -   323—eighth channel forming embodiment formed through port 359 in        second end plate 312, and apertures 111, 80, 107, 379, 107, and        80;    -   334—second of two end clamping plates (also referred to as an        end plate);    -   350—Basic double CCF Frame (“double” electrically conductive        metal frame circulation chamber and current carrier utilized in        the assembly stack in FIG. 7 )    -   348—first tubular port for feeding or extracting products        to/from end plate 334;    -   357—second tubular port for feeding or extracting products        to/from end plate 334;    -   351—third tubular port for feeding or extracting products        to/from end plate 334;    -   353—fourth tubular port for feeding or extracting products        to/from end plate 334;    -   349—(top) first tubular port for feeding or extracting products        to/from end plate 312;    -   359—(bottom) second tubular port for feeding or extracting        products to/from end plate 312;    -   355—(top) third tubular port for feeding or extracting products        to/from end plate 312;    -   356—(bottom) fourth tubular port for feeding or extracting        products to/from end plate 312; (not shown but equivalent to 353        in 434);    -   398—first channel defining aperture in frame 21;    -   399—third channel defining aperture in frame 21;    -   FIG. 8A: Double CCF    -   FIG. 8B: Double CCF with Electroactive Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   66—first notch;    -   67—second notch;    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103    -   304—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 378;    -   305—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 379;    -   314—strut delimiting the apertures 352 and 354 at first end of        frame 350, 368, 374, 385;    -   315—strut delimiting the apertures 378 and 380 at second end of        frame 350, 368, 374, 385;    -   332—central axis of frame 350, 368, 374, 385, 450, 550, wherein        current enters both of the product circulation chambers 103;    -   350—Basic double CCF Frame (“double” electrically conductive        metal frame circulation chamber and current carrier utilized in        the assembly stack in FIG. 7 );    -   352—first channel defining aperture of frame 350, 368, 374, 385;    -   353—short side section of frame 350, 368, 374, 385, 450, 550;    -   354—third channel defining aperture of frame 350, 368, 374, 385;    -   355—seventh channel defining aperture of frame 350, 368, 374,        385;    -   356—fifth channel defining aperture of frame 350, 368, 374, 385;    -   360—strut delimiting the apertures 379 and 381 at second end of        frame 350, 368, 374, 385;    -   363—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 354;    -   378—fourth channel defining aperture in frame 350, 368, 374,        385;    -   379—eighth channel defining aperture in frame 350, 368, 374,        385;    -   380—second channel defining aperture in frame 350, 368, 374,        385;    -   381—sixth channel defining aperture of frame 350, 368, 374, 385;    -   382—strut delimiting the apertures 356 and 355 at first end of        frame 350, 368, 374, 385;    -   383—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 355;

FIG. 9A: Double CCF with “Dog Bones”

-   -   FIG. 9B: Double CCF with “Dog Bones” and Electroactive        Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   66—first notch;    -   67—second notch;    -   69—Big dog bones (removable electrically conductive struts        across circulation chamber 103);    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103    -   304—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 378;    -   305—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 379;    -   314—strut delimiting the apertures 352 and 354 at first end of        frame 350, 368, 374, 385;    -   315—strut delimiting the apertures 378 and 380 at second end of        frame 350, 368, 374, 385;    -   332—central axis of frame 350, 368, 374, 385, 450, 550, wherein        current enters both of the product circulation chambers 103;    -   352—first channel defining aperture of frame 350, 368, 374, 385;    -   353—short side section of frame 350, 368, 374, 385, 450, 550;    -   354—third channel defining aperture of frame 350, 368, 374, 385;    -   355—seventh channel defining aperture of frame 350, 368, 374,        385;    -   356—fifth channel defining aperture of frame 350, 368, 374, 385;    -   360—strut delimiting the apertures 379 and 381 at second end of        frame 350, 368, 374, 385;    -   363—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 354;    -   368—to double CCF with dog bones (electrically conductive metal        frame circulation chamber and current carrier with removable        conductive struts with manufactured channels that can be        equivalently utilized in the assembly stack in FIG. 7 );    -   378—fourth channel defining aperture in frame 350, 368, 374,        385;    -   379—eighth channel defining aperture in frame 350, 368, 374,        385;    -   380—second channel defining aperture in frame 350, 368, 374,        385;    -   381—sixth channel defining aperture of frame 350, 368, 374, 385;    -   382—strut delimiting the apertures 356 and 355 at first end of        frame 350, 368, 374, 385;    -   383—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 355;    -   FIG. 10A: Double CCF with Conductive Spears    -   FIG. 10B: Double CCF with Conductive Spears and Electroactive        Structures    -   FIG. 10C: Double CCF with Alternative Spears    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   66—first notch;    -   67—second notch;    -   76—“Spears” of single CCF 374 (diagonally oriented rod-like        protrusions provided as part of 374, located adjacent to where        power is to be provided in the frame);    -   76A—an alternate embodiment of spears 76;    -   79—cut-outs provided in a CCF;    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103    -   304—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 378;    -   305—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 379;    -   314—strut delimiting the apertures 352 and 354 at first end of        frame 350, 368, 374, 385;    -   315—strut delimiting the apertures 378 and 380 at second end of        frame 350, 368, 374, 385;    -   332—central axis of frame 350, 368, 374, 385, 450, 550, wherein        current enters both of the product circulation chambers 103;    -   352—first channel defining aperture of frame 350, 368, 374, 385;    -   353—short side section of frame 350, 368, 374, 385, 450, 550;    -   354—third channel defining aperture of frame 350, 368, 374, 385;    -   355—seventh channel defining aperture of frame 350, 368, 374,        385;    -   356—fifth channel defining aperture of frame 350, 368, 374, 385;    -   360—strut delimiting the apertures 379 and 381 at second end of        frame 350, 368, 374, 385;    -   363—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 354;    -   374—double CCF with spears (electrically conductive metal frame        circulation chamber and current carrier with conductive spears        that can be equivalently utilized in the assembly stack in FIG.        7 );    -   374A—CCF 374 employing spears 76A;    -   378—fourth channel defining aperture in frame 350, 368, 374,        385;    -   379—eighth channel defining aperture in frame 350, 368, 374,        385;    -   380—second channel defining aperture in frame 350, 368, 374,        385;    -   381—sixth channel defining aperture of frame 350, 368, 374, 385;    -   382—strut delimiting the apertures 356 and 355 at first end of        frame 350, 368, 374, 385;    -   383—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 355;    -   FIG. 11A: Double CCF with Conductive Struts    -   FIG. 11B: Double CCF with Conductive Struts and Electroactive        Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   58—electrically conductive struts across circulation chamber        103;    -   60—portion of strut 58 which is a channel defining strut        section;    -   62—raised portions of struts 58 used as attachment points for        the electroactive structure;    -   66—first notch;    -   67—second notch;    -   76—“Spears” of single CCF 374 (diagonally oriented        spear-protrusions provided as part of 374, located adjacent to        where power is to be provided in the frame);    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103    -   304—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 378;    -   305—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 379;    -   314—strut delimiting the apertures 352 and 354 at first end of        frame 350, 368, 374, 385;    -   315—strut delimiting the apertures 378 and 380 at second end of        frame 350, 368, 374, 385;    -   332—central axis of frame 350, 368, 374, 385, 450, 550, wherein        current enters both of the product circulation chambers 103;    -   352—first channel defining aperture of frame 350, 368, 374, 385;    -   353—short side section of frame 350, 368, 374, 385, 450, 550;    -   354—third channel defining aperture of frame 350, 368, 374, 385;    -   355—seventh channel defining aperture of frame 350, 368, 374,        385;    -   356—fifth channel defining aperture of frame 350, 368, 374, 385;    -   360—strut delimiting the apertures 379 and 381 at second end of        frame 350, 368, 374, 385;    -   363—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 354;    -   378—fourth channel defining aperture in frame 350, 368, 374,        385;    -   379—eighth channel defining aperture in frame 350, 368, 374,        385;    -   380—second channel defining aperture in frame 350, 368, 374,        385;    -   381—sixth channel defining aperture of frame 350, 368, 374, 385;    -   382—strut delimiting the apertures 356 and 355 at first end of        frame 350, 368, 374, 385;    -   383—first delimiting conducting strut between circulation        chamber 103 and channel defining aperture 355;    -   385—to double CCF with rungs (electrically conductive metal        frame circulation chamber and current carrier with conductive        struts with channels that can be equivalently utilized in the        assembly stack in FIG. 7 );    -   FIG. 12 : Isometric Full Assembly of Single CCFs with Additional        Transfer Passages    -   410—the assembled stack of single CCFs with additional product        transfer passageways    -   412—first of two end clamping plates (also referred to as an end        plate);    -   414—first full faced gasket with three pathways;    -   416—first channel forming embodiment comprising port 449 in end        clamping plate 412, and apertures 494 in gasket 414, 493 in CCF        450, 460 in gasket 430, 488 in CCF 450, 460, and 493;    -   417—second channel forming embodiment comprising port 459 in end        plate 412, and apertures 495, 480, 461, 478, 461, 480;    -   418—third channel forming embodiment comprising port 452 in end        plate 412, and apertures 496, 492, 462, 489, 462, and 492;    -   419—fourth channel forming embodiment comprising port 457 in end        plate 434, and apertures 495, 478, 463, 480, 463, 480;    -   420—fifth channel forming embodiment comprising port 451 in end        plate 434, 496, 489, 464, and 492;    -   421—sixth channel forming embodiment comprising port 448 in end        clamping plate 434, and apertures 494, 488, 465, 493;    -   430—sealing and electrically insulating gasket between CCF's of        different polarities;    -   422, 424—masking frames;    -   434—second of two end clamping plates (also referred to as an        end plate);    -   450—assigned to single CCF with multiple passageways        (electrically conductive metal frame circulation chamber and        current carrier with additional passageways for product and        reactant input and output, utilized in multiple passageways        stack FIG. 12 );    -   448—first tubular port for feeding or extracting products        to/from end plate 434;    -   457—second tubular port for feeding or extracting products        to/from end plate 434;    -   449—first tubular port for feeding or extracting products        to/from end plate 412;    -   459—second tubular port for feeding or extracting products        to/from end plate 412;    -   51—third tubular port for feeding or extracting products to/from        end plate 434;    -   452—third tubular port for feeding or extracting products        to/from end plate 412;    -   460—first aperture in gasket 430;    -   461—second aperture in gasket 430;    -   462—third aperture in gasket 430;    -   463—fourth aperture in gasket 430;    -   464—fifth aperture in gasket 430;    -   465—sixth aperture in gasket 430;    -   494—first channel defining aperture in gasket 414;    -   495—(bottom) second channel defining aperture in gasket 414;    -   496—(middle) third channel defining aperture in gasket 414;    -   FIG. 13A: Single CCF with Multiple Transfer Passageways    -   FIG. 13B: Single CCF with Multiple Transfer Passageways and        Electroactive Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   53—short side section of frame 50, 68, 74, 85, 450;    -   64—electrically conductive tab for connection to a source of        power;    -   66—first notch;    -   67—second notch;    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103    -   404—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 478;    -   415—strut delimiting the apertures 478 and 480 at second end of        frame 450;    -   450—assigned to single CCF with multiple passageways        (electrically conductive metal frame circulation chamber and        current carrier with additional passageways for product and        reactant input and output, utilized in multiple passageways        stack FIG. 12 );    -   478—fourth channel defining aperture in frame 450;    -   480—second channel defining aperture in frame 450;    -   481—first delimiting conducting strut between circulation        chamber 103 and channel defining apertures 493, 492, 489, and        488;    -   483—opening provided between 487 and 481 to allow liquid from        493 to flow into 492;    -   484—fifth delimiting conducting strut between channel defining        apertures 488 and 489 and first delimiting conducting strut 481;    -   486—fourth delimiting conducting strut between channel defining        apertures 489 and 492 and first delimiting conducting strut 481;    -   487—third delimiting conducting strut between channel defining        apertures 492 and 493 and first delimiting conducting strut 481;    -   488—sixth channel defining aperture;    -   489—fifth channel defining aperture;    -   492—third channel defining aperture;    -   493—first channel defining aperture;    -   FIG. 14 : Isometric Full Assembly of Double-Single CCFs with        Additional Transfer Passages    -   510—the assembled stack of single and double CCFs with        additional product transfer passageways;    -   512—first of two end clamping plates (also referred to as an end        plate);    -   534—second of two end clamping plates (also referred to as an        end plate);    -   550—double CCF with multiple passageways (electrically        conductive metal frame circulation chamber and current carrier        with additional passageways for product and reactant input and        output, utilized in multiple passageways stack FIG. 14 );

Connecting to End Plate 512

-   -   516—first channel forming embodiment comprising port 549 in        first end clamping plate 512, and apertures 494, 488, 460, 593        in double CCF 550;    -   517—second channel forming embodiment comprising port 559 in        first end plate 512 (obscured by first right-hand gasket 414),        495, 478, 461 (obscured by electroactive structure), and 580 in        the anodically polarized side of CCF 550;    -   518—third channel forming embodiment comprising port 555 in        first end plate 512, and apertures 496, 489, 462, 592;    -   525—tenth channel forming embodiment comprising port 556 in        second end plate 512, and apertures 495, 480, 461, 558, 461,        480;    -   526—eleventh channel forming embodiment comprising port 546 in        second end plate 512, 496, 492, 462, 569, 462, and 492;    -   527—twelfth channel forming embodiment comprising port 547 in        second end clamping plate 512, and apertures 494, 493, 460, 568,        460, 493;    -   549—tubular port for feeding or extracting products to/from end        plate 512 via first channel 516;    -   559—tubular port for feeding or extracting products to/from end        plate 512 via second channel 517; (NOT SHOWN)    -   555—tubular port for feeding or extracting products to/from end        plate 512 via third channel 518;    -   556—tubular port for feeding or extracting products to/from end        plate 512 via tenth channel 525;    -   546—tubular port for feeding or extracting products to/from end        plate 512 via eleventh channel 526;    -   547—tubular port for feeding or extracting products to/from end        plate 512 via twelfth channel 527;

Connecting to End Plate 534

-   -   519—fourth channel forming embodiment comprising port 553 in        first end plate 534, obscured aperture 495 in gasket 414, 480,        463, 578, 463, and 480;    -   520—fifth channel forming embodiment comprising port 554 in        first end plate 534, 496, 492, 464, 589, 464, 492;    -   521—sixth channel forming embodiment comprising port 552 in        first end plate 534, and apertures 494, 493, 465, 588, 465, and        493;    -   522—seventh channel forming embodiment comprising port 548 in        second end plate 534, and apertures 494, 488, 465, and 573;    -   523—eighth channel forming embodiment comprising port 557 in        second end plate 534, and apertures 495, 478, 463, and 560;    -   524—ninth channel forming embodiment comprising port 551 in        second end plate 534, and apertures 496, 489, 464, and 572;    -   548—tubular port for feeding or extracting products to/from end        plate 534 via seventh channel 522;    -   557—tubular port for feeding or extracting products to/from end        plate 534 via eighth channel 523;    -   551—tubular port for feeding or extracting products to/from end        plate 534 via ninth channel 524;    -   552—tubular port for feeding or extracting products to/from end        plate 534 via sixth channel 521;    -   553—tubular port for feeding or extracting products to/from end        plate 534 via fourth channel 519;    -   554—tubular port for feeding or extracting products to/from end        plate 534 via fifth channel 520;    -   FIG. 15A: Double CCF with Additional Transfer Passages    -   FIG. 15B: Double CCF with Additional Transfer Passages and        Electroactive Structures    -   44—non-limiting example of a planar electroactive structure,        comprising a continuous expanded metal sheet;    -   51—long side section of frames 50, 68, 74, 85, 350, 368, 374,        385, 450, 550;    -   353—short side section of frame 50, 68, 74, 85, 450;    -   66—first notch;    -   67—second notch;    -   103—circulation chamber, provided by the CCF depth;    -   103A—depth dimension of circulation chamber 103;    -   332—central axis of frame 350, 368, 374, 385, 450, 550, wherein        current enters both of the product circulation chambers 103;    -   353—short side section of frame 350, 368, 374, 385, 450, 550;    -   504—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 578;    -   515—strut delimiting the apertures 578 and 580 at second end of        frame 550;    -   550—to double CCF with multiple passageways (electrically        conductive metal frame circulation chamber and current carrier        with additional passageways for product and reactant input and        output, utilized in multiple passageways stack FIG. 14 );    -   535—strut delimiting the apertures 558 and 560 at second end of        frame 550;    -   540—second delimiting conducting strut between circulation        chamber 103 and channel defining aperture 558;    -   558—tenth channel defining aperture in frame 550;    -   560—eighth channel defining aperture in frame 550;    -   561—first delimiting conducting strut between circulation        chamber 103 and channel defining apertures 573, 572, 569, and        568;    -   563—opening provided between 567 and 561 to allow liquid from        573 to flow into 572;    -   564—eighth delimiting conducting strut between channel defining        apertures 568 and 569 and first delimiting conducting strut 561;    -   566—seventh delimiting conducting strut between channel defining        apertures 569 and 572 and first delimiting conducting strut 561;    -   567—sixth delimiting conducting strut between channel defining        apertures 572 and 573 and first delimiting conducting strut 561;    -   568—twelfth channel defining aperture;    -   569—eleventh channel defining aperture;    -   572—ninth channel defining aperture;    -   573—seventh channel defining aperture;    -   578—fourth channel defining aperture in frame 550;    -   580—second channel defining aperture in frame 550;    -   581—first delimiting conducting strut between circulation        chamber 103 and channel defining apertures 593, 592, 589, and        588;    -   583—opening provided between 587 and 581 to allow liquid from        593 to flow into 592;    -   584—fifth delimiting conducting strut between channel defining        apertures 588 and 589 and first delimiting conducting strut 581;    -   586—fourth delimiting conducting strut between channel defining        apertures 589 and 592 and first delimiting conducting strut 581;    -   587—third delimiting conducting strut between channel defining        apertures 592 and 593 and first delimiting conducting strut 581;    -   588—sixth channel defining aperture;    -   589—fifth channel defining aperture;    -   592—third channel defining aperture;    -   593—first channel defining aperture;    -   FIG. 16A: Top Down View—Unipolar Single Stack Current Flow    -   FIG. 16B: Top Down View—Unipolar Double Stack Current Flow    -   FIG. 16C: Top Down View—Scaled Unipolar CCFs Cell Block        Embodiment    -   50—Basic single CCF    -   26—electrically conductive mesh, perforated or slotted sheet,        expanded sheet, screens, woven mesh or similar appropriate        planar configuration thereof forming the cathodic electroactive        structure with the − sign in FIG. 2 ;    -   28—separator;    -   30—sealing and electrically insulating gasket between CCF's of        different polarities;    -   102—electrically conductive mesh, perforated or slotted sheet,        expanded sheet, screens, woven mesh or similar appropriate        planar configuration thereof forming the anodic electroactive        structure and designated as an anodic mesh with the + sign in        FIG. 2 ;    -   350—Basic double CCF.

FIG. 1A illustrates a top-down view and cross section of theelectroactive regions of a basic unipolar current carrying configurationshown generally by the half-cell at 210 with electroactive structuresattached. The unipolar current carrying configuration comprises anelectrical current carrying structure 212 that provides multipleelectroactive structures 102 of the same polarity on opposing sides ofthe current carrying structure 212, such that regions of the sameuniversal polarity 226 are provided on the opposing sides of the currentcarrying structure 212, and such that current is provided by a powersource 214 and flows across in the direction of arrow 216 in the currentcarrier 212 and to electroactive structures 102. Typically, the currentflows in a parallel direction to the electroactive structures 102 fromleft to right. The half-cell in FIG. 1A creates the base currentcarrying unit for a unipolar electrochemical filter press deviceconstructed of positive and negative half-cell pairs.

FIG. 1B illustrates a top-down view and cross section of theelectroactive region of a basic monopolar current carrying configurationshown generally by the half-cell at 218 with an electroactive structureattached. The monopolar current carrying configuration comprises anelectrical current carrying structure 212 that provides an electroactivestructure 102 of a singular polarity on one side of the current carryingstructure 212, such that a region of one polarity 226 is provided on theside of the current carrying structure 212 that possesses theelectroactive structure 102, and such that current is provided by apower source 214 and flows across in the direction of arrow 216 in thecurrent carrier 212 and to the electroactive structure 102. Typically,the current flows in a parallel direction to the electroactive structure102 from left to right. The half-cell in FIG. 2A creates the basecurrent carrying unit for a monopolar electrochemical filter pressdevice constructed of positive and negative half-cell pairs.

FIG. 1C illustrates a top-down view and cross section of theelectroactive regions of a basic bipolar current carrying configuration,shown generally at 220. The bipolar current carrying configurationcomprises a bipolar wall 222 defining electroactive areas of oppositepolarity on opposing sides of the current carrying structure, such thatregions of opposite polarity (226, 228) are provided on the opposingsides of the bipolar wall 222, and such that current is provided by apower source 214 and flows through the bipolar wall orthogonally 224,creating the base current carrying unit for a bipolar electrochemicalfilter press device. Cells within a bipolar filter press areelectrically connected in series, with each individual current carriertypically comprising one anodic side and one cathodic side connected bythe conductive bipolar wall. The bipolar wall 222 is a non-porouselectrically conductive wall with electrodes separating the anodic andcathodic halves. Naturally this cannot be porous, as that would allow Oand H to mix which is dangerous in the case of water electrolysis, andcross-contaminate the anolyte and catholyte which is undesirable incaustic chlorine electrolysis.

All of the unipolar electrochemical device embodiments presented in thisdisclosure (for example 10 in FIG. 2, 310 in FIG. 7, 410 in FIG. 12, 510in FIG. 14 ) may be utilized for a variety of electrochemical processes.Preferred examples of processes include: alkaline water electrolysis,and chlorine production through chlor alkali and sodium chlorateelectrolysis. In all such electrolysis processes, electrolyte exposed toa cathode in the cathodically polarized region of the cell is referredto as “catholyte,” whereas the electrolyte exposed to an anode in theanodically polarized region of the cell is referred to as “anolyte.”

In alkaline water electrolysis, (whose reactions are well known to thoseskilled in the art), the starting electrolyte is comprised of a highlybasic sodium hydroxide or potassium hydroxide solution. The anodeproduct created is oxygen gas, and the cathode product created ishydrogen gas. Catholyte and any additional reactants required are fedinto the cathodic end of the filter press stack, and anolyte and anyadditional reactants required are fed into the anodic end of the stacksuch that target concentrations are achieved.

In chlorine electrolysis, the starting electrolyte is comprised ofsodium chloride in water, referred to as “brine.” The anode product isgaseous chlorine, and the cathode products are hydrogen gas and sodiumhydroxide. In sodium chlorate production processes, chlorineelectrolysis is completed without a separator (i.e. embodimentsidentical to those presented herein however without a separator 28 asdescribed later), such that the chlorine and sodium hydroxide are notseparated. When chlorine and sodium hydroxide are not separated(referred to as “sodium chlorate electrolysis”) the chlorine anodeproduct reacts with the sodium hydroxide cathode products giving sodiumhypochlorite (NaOCl) which gets removed and reacted to produce sodiumchlorate NaClO₃.

When a separator is applied in a chlorine cell (referred to as the“chlor alkali process”) and said separator is often provided as acation-exchange membrane, this cation exchange membrane separates theanolyte and catholyte. Brine is fed into the anode plate, and sodiumions and water molecules migrate through the membrane into thecatholyte. Chloride ions are prevented from moving into the catholyte bythe membrane. The anode product is still gaseous chlorine, and thecathode products are still hydrogen gas and sodium hydroxide. Aseparator diaphragm may be applied in place of a membrane in olderchlorine cells, where the anolyte is physically separated from thecatholyte through a mass-transport process rather than an ion-transportprocess, and there is a bulk flow of anolyte through the diaphragm tothe catholyte.

In membrane chlorine electrolysis processes, brine that has been reducedin concentration (“depleted brine”) is removed from the anode plate,resaturated with salt to ensure the required salt concentration ismaintained, and fed back into the cell. At the cathode, water iselectrolyzed to form hydrogen and hydroxyl ions to form caustic sodawhen combined with sodium ions. Gas liquid separation of products andthe recirculation and resaturation of anolyte can be achieved outside ofthe electrolytic cell, or inside the electrolytic cell depending on theconstraints of the cell design and application. The chlor alkali processand the sodium chlorate production process are well known to thoseskilled in the art of electrolysis, as their chemical products(chlorine, hydrogen, caustic soda) are sold into a wide array ofchemical industries to create well known products such as bleach (madefrom chlorine), hydrochloric acid, and hydrogen peroxide (made fromhydrogen).

The growing momentum of the Hydrogen Economy in recent years furtherreinforces the need for scalable economic industrial electrolysisprocesses such as alkaline water electrolysis to be applied in theproduction of hydrogen for both traditional and emerging applications.The unipolar electrochemical devices presented herein are particularlypreferred when applied to large scale alkaline water electrolysis.

FIG. 2 illustrates a disassembled view of a unipolar filter presselectrolyser assembly 10 (or “unipolar filter press stack”) based on thecurrent carrier, circulation chamber, and frame (“CCF”) of FIG. 3A. Theunipolar assembly shown in FIG. 2 is equivalent to one unipolarelectrochemical filter press stack, as a single circuit.

An important clarification to make in describing unipolar filter pressstacks based on CCF technology is the definition of a singleelectrochemical cell. The unipolar filter press stack 10 (and 410described later) each represent one (1) electrochemical cell, configuredelectrically in parallel. To increase the surface area for productgeneration within one unipolar electrochemical cell, additional anodicand cathodic CCFs are simply added to the filter press stacklongitudinally. All cathodic CCFs provided are connected externally inparallel, and similarly all anodic CCFs provided are connectedexternally in parallel. Even after the provision of additional CCFslongitudinally within a unipolar filter press stack, the stack remainsas one electrochemical cell, now with increased surface area per cell.

This contrasts the analogous situation in bipolar filter presses whichare configured electrically in series. In bipolar filter presses, witheach longitudinal addition of a bipolar electrode assembly (such as thatshown in FIG. 1C), the number of electrochemical cells within the filterpress is increased. Consequently, the total voltage of the bipolarfilter press in series is increased, without having increased thesurface area for product generation per electrochemical cell.

Increasing the surface area per electrochemical cell is highly desiredin the field of large-scale alkaline water electrolysis, so to increasethe product output and overall efficiency of an electrolyser design.With increases in surface area per electrochemical cell, greateramperage per cell is enabled, consequently allowing greater hydrogenproduct generation according to the well-known Faraday's Law ofElectrolysis. This makes unipolar filter press technology based on CCF'sparticularly desirable for the application of large-scale alkaline waterelectrolysis where large increases in surface area per electrochemicalcell are required to efficiently scale product generation.

Unipolar filter press assemblies wherein two unipolar filter pressstacks (creating proportionally two electrochemical cells) are providedwithin the same filter press assembly (310 and 510) are described later.Such filter press assemblies as 310 and 510 can also be scaledlongitudinally by providing additional CCF's within each filter pressstack to increase surface area per cell, as described later and shown inFIG. 16C. Such multi-cell assemblies can also be scaled laterally toproportionally increase the number of electrochemical cells perassembly, also described later and shown in FIG. 16C.

The features of the unipolar filter press stack 10 shown in FIG. 2 aredescribed herein in more detail.

Within the stack 10, two unipolar positive and two monopolar negativeelectrochemical reaction regions are electrically configured inparallel, creating a total of four electrochemically active regions. Forease of comprehension but not limiting other possibilities, CCF 20described further below is construed as being of positive polarity andCCF's 21 are construed as being of negative polarity. Unipolar CCF 20provides two electrochemical reaction regions of the same polarity (asdefined in FIG. 1A), while each monopolar CCF 21 provides oneelectrochemical reaction region of a single polarity (as defined in FIG.1B). Therefore, the assembly shown in FIG. 2 has a total of fourelectroactive regions, being comprised of one unipolar CCF and twomonopolar CCFs.

The negative electrochemical reaction regions are localized between theelectroactive surface of structure 26 (negative) of monopolar CCFs 21and the separators 28, all as shown adjacent to end gaskets 14.Electrically in parallel to both negative electrochemical reactionregions, two positive electrochemical reaction regions are localized atunipolar CCF 20, as defined by the two electroactive structures 102(positive) of unipolar CCF 20.

A conductive chamber for product circulation (“circulation chamber”) 103within each electrochemical reaction region is provided by the thickness(“depth”) of CCFs 20 and 21 themselves, the depth being indicated inFIG. 3A at 103A. No additional parts are required to create depth forproduct circulation in the assembly, thereby reducing the total partcount of this unipolar filter press stack. This depth for productcirculation 103A may vary as required by the underlying application andconstraints of the design space, and is provided for all CCF embodimentspresently described, the advantages of which are discussed later.

For ease of comprehension, the assembly in FIG. 2 is simplified toinclude only three total CCFs; the central CCF 20 being in a unipolarconfiguration and CCFs 21 adjacent to end gaskets 14 and end plates 12and 34 respectively being in a monopolar configuration. Three is theminimum number of CCFs required to assemble an electrolyser. Thosefamiliar with the electrochemical domain will understand that additionalelectrochemical reaction regions within the same unipolar filter pressstack can be obtained by an adequate assembly of the components listedin the present disclosure, as described later.

As well, those familiar with the electrochemical domain will understandthat monopolar CCF 21 as illustrated in FIG. 2 can have electroactivestructures 26 attached on both faces, such as to be in a unipolarconfiguration and essentially identical to CCF 20, except for thepolarity of CCF 20 being opposite to CCF 21. Such a unipolar CCF 21could thus be inserted into a larger assembly than that illustrated inFIG. 2 .

Those skilled in the design of electrolysers will further comprehendthat the terminal (or “end-most”) monopolar CCFs 21 shown in FIG. 2 areadjacent to sealing gaskets 14, and therefore do not require theadditional product-generating electroactive structures 26 that wouldconvert the monopolar CCF 21 into a unipolar CCF 21. For this reason,those skilled in the design of electrolysers will understand thatmonopolar CCFs are most practical in the end-most position, adjacent tothe stack's end assembly, and that practically only unipolar CCFs wouldbe provided longitudinally to scale the assembly, increasing the surfacearea per electrochemical cell, as discussed.

For ease of comprehension, the parts that must be employed toincorporate more CCFs longitudinally in the filter press assembly of 10are described below.

In one embodiment, a unipolar CCF 21 could be substituted to the secondmonopolar CCF 21 illustrated in FIG. 2 , such as to permit forming oneadditional electrochemical reaction region with the additionalelectroactive structure 26 provided by the substituted unipolar CCF 21.Following this insertion with the insertion of the correspondingnon-limiting components (a corresponding separator 28 and gasket 30 tocomplement the shown masks (22, 24)), then the insertion of a positiveunipolar CCF 20 (provided with two electroactive structures 102),followed by the corresponding non-limiting components (a correspondingseparator 28 and gasket (30) and masks (22, 24)), then finally theinsertion of a terminal monopolar CCF 21 with corresponding masks (22,24), a unipolar filter press single electrochemical cell with eightelectrochemically active regions would be assembled.

To scale this assembly further, insertions in the 10's or 100's ofalternating unipolar CCFs 21 (negative) and 20 (positive) and theircorresponding non-limiting masks (22, 24), gaskets 30, and separators 28may be inserted into the stack centre before the terminal monopolar CCF21. The quantity of electrochemically active regions (surface area)within a singular unipolar filter press stack will scale with theaddition of each CCF, overall providing a proportionally scaled singleunipolar cell within a filter press assembly, electrically configured inparallel.

The electrolyser device embodiment 10 in FIG. 2 further depicts tworigid end clamping plates 12 and 34 adjacent to full faced sealing endgaskets 14. Those skilled in the electrochemical domain will understandthat to assemble and seal the filter press 10 in FIG. 2 such that leaksare prevented in operation, a compression system such as a hydraulicpress or other clamping means is required. One exemplary compressionsystem comprises the application of a filter press clamping device,known to those skilled in the electrochemical domain, which wouldmechanically seal all of the components between clamping end plates 12and 34. To input reactants and collect product from this system,discharge and feed channels (49, 59 in plate 12 and 48, and 57 in plate34) would be attached to some external piping elements on the plates 12and 34. Those familiar with the electrochemical domain will understandthat the clamping end plates 12 and 34 shown for use with a filter pressclamping device are non-limiting in this disclosure. Those skilled inthe electrochemical domain will further understand that in certainfilter press stack configurations, tie rods may be used to alignassembly components within the filter press stack. Under suchcircumstances, tie rod holes can be provided within one or both longsides 51 or 55 of any of the CCFs shown in FIGS. 3 to 6 and 13 . For thesame purpose, tie rod holes may be optionally provided on either longsides 51, or central axis 332 of CCFs shown in FIGS. 8 to 11 and 15 asnecessitated by the engineering requirements of the design.

In this disclosure, FIG. 2 and FIG. 3A depict CCF's 20 and 21 featuringapertures 52 and 80 (and 54 and 78) disposed diagonally at either end ofproduct circulation chamber 103. Those familiar with the electrochemicaldomain will understand that this is not a limiting feature as therelative position of the feed/discharge channels can be different.Consequently, the apertures of other non-limiting pieces such as gaskets14 may be adjusted according to the position of the apertures within theCCF. The two generally rectangular adjacent apertures at both ends ofCCF's 20 and 21 and frame gaskets 30 align with each other and thecorresponding apertures in gasket 14 when the electrolyser is assembled.

To help in the comprehension of the functional arrangement of theassembled electrolyser 10, the parts of which are shown detached in FIG.2 , a brief explanation of the relative positioning of the parts andtheir function is given.

While all these parts are shown separated from each other, in theassembled unipolar filter press electrolyser 10 the two (2)electroactive structures 102 located on either side of CCF 20 areelectrically connected to either side of CCF 20. The electroactivestructures 26 adjacent to the two outer CCF's 21 are similarly connectedto their respective CCF.

As discussed, electrolyser 10 includes two preferably rigid end clampingplates 12 and 34. First and second full faced gaskets 14 each have two(2) apertures extending therethrough at diagonal corners of the gasket.First gasket 14 is “sandwiched” between end clamping plate 12 and firstmonopolar CCF 21. Second gasket 14 is sandwiched between end clampingplate 34 and second monopolar CCF 21. The apertures in first gasket 14(apertures 110 and 111) align with the ports in end clamping plate 12(49 and 59). Similarly, the apertures in second gasket 14 (apertures 94and 109) align with the ports in end clamping plate 34 (48 and 57).Gaskets 14 are additionally in alignment with channel defining pathwaysfor product and reactants in the respective CCFs 21, to be describedlater.

The pathways for products and reactants, or transfer channels 116, 117,118, 119 are better visualized when described as explained below.

Reading from right to left on FIG. 2 , first channel 116 is formed andpasses through port 48 in end plate 34, and apertures 94, 98, 106, and52, where all fluids collected or fed to are generally anodic. Maskingof the cathodic CCF 21 the channel 116 passes through is provided bymask 22.

Similarly, reading from right to left on FIG. 2 , second channel 117 isformed passing through port 57 in second clamping plate 34, andapertures 109, 101, 107, and 80 where all fluids collected or fed to aregenerally anodic. Masking of the cathodic CCF 21 the channel 117 passesthrough is provided by mask 24.

Reading from left to right on FIG. 2 , third channel 118 is formedpassing through port 49 in end plate 12, and apertures 110, 99, 90, 54,90, and 99, where all fluids collected or fed to are generally cathodic.Masking of the anodic CCF 20 the channel 118 passes through is providedby mask 22.

Reading from left to right on FIG. 2 , fourth channel 119 is formedpassing through port 59 in end plate 12, 111, 100, 108, 78, 108 and 100.Masking of the anodic CCF 20 the channel 119 passes through is providedby mask 24. For simplicity, masks 22 and 24 are not used in thedefinition of the transfer passageways of future embodiments describedlater on, however they are provided as part of the transfer passagewaysas shown in the Figures.

The height of the apertures that define product transfer passageways116, 117, 118, and 119 (along with the product transfer passageways ofany of the other electrolyser embodiments described herein) may befurther adjusted as required by the underlying electrochemical process,and application of the filter press stack.

Moving left to right in FIG. 2 a first CCF 21 is positioned againstfirst gasket 14 followed by electroactive structure 26 and separator 28.A first set of masks 22 and 24 is inserted within channel apertures 98and 101 of CCF 21, and a first set of channel-defining gasket supportpieces 56 are inserted by friction fit at exemplary friction-fitinsertion points 56A (shown in FIG. 3A) configured to receive a frictionfit gasket support piece to complete the definition of apertures 100 and99 in first CCF 21. Insertion points 56A for gasket support pieces arenon-limiting and may be provided in alternative embodiments asnecessitated by the gasket support piece. Gasket support pieces 56control product and reactant passage into and out of apertures 100 and99 in first CCF 21 through channels of a defined size, and support thestructural integrity of the corresponding apertures 90 and 108 in afirst gasket 30 when the system is clamped, such that transfer channels118 and 119 are reinforced and products and reactants are controlledwithin their corresponding transfer channel.

First gasket 30 is positioned against the right hand face of CCF 21followed by first electroactive structure 102 on the left hand face ofCCF 20. A second electroactive structure 102 on the right hand face ofCCF 20, a second separator 28, and second set of channel defining gasketsupport pieces 56 to complete apertures 52 and 80 in first CCF 20,follow. The second set of channel defining gasket support pieces 56support the structural integrity of the corresponding apertures 106 and107 in second gasket 30 when the system is clamped, such that transferchannels 116 and 117 are reinforced and products and reactants arecontrolled within their corresponding transfer channel. Gasket supportpieces 56 further control product and reactant passage into and out ofapertures 52 and 80 in second CCF 20 through the provision of channelsof a defined size. A second set of masking frames 22 and 24 is insertedwithin corresponding channel defining apertures 54 and 78 of CCF 20. Asecond gasket 30 is positioned against the right hand face of CCF 20.

A second electroactive structure 26 is positioned between second gasket30 and the left hand face of second CCF 21. A third set of maskingframes 22 and 24 is inserted within corresponding channel definingapertures 98 and 101 of CCF 21, and a third set of channel defininggasket support pieces 56 are inserted to complete apertures 100 and 99in second CCF 21. The third set of channel defining gasket supportpieces support the structural integrity of the corresponding apertures90 and 108 in second gasket 30 when the system is clamped, such thattransfer channels 118 and 119 are reinforced, and products and reactantsare controlled within their corresponding transfer channel. Gasketsupport pieces 56 further control product and reactant passage into andout of apertures 100 and 99 in second CCF 21 through the provision ofchannels of a defined size. A second full faced gasket 14 is sandwichedbetween second CCF 21 and the second end clamping plate 34.

The function of masks 22 and 24 is dual fold: for load distribution whenthe electrolyser is clamped, and to prevent the electrically chargedfluids of one polarity from being in contact with the metallic CCF ofthe opposite polarity, in order to prevent undesired electrolyticreactions within the four transfer channels 116, 117, 118 and 119.Adjacent first and third channels are electrically insulated by mask 22,for example placed in third aperture 54 of CCF 20. Similarly, forproviding electrical insulation between adjacent second and fourthchannels, mask 24 is placed in fourth aperture 78 of CCF 20.

The purpose of gaskets 30 is to provide a means for sealing theperiphery of the circulation chamber 103 and that of the four adjacentapertures between the internal pressure of system 10 and externalatmospheric pressure. Gaskets 30 are also required to distribute loadwithin the filter press stack. In an alternate embodiment, said maskingframes (22, 24) are placed within the apertures of the sealing andelectrically insulating gaskets 30, such that they align with theircorresponding product transfer passageways, rather than being placed inthe apertures of the CCF itself.

When the system is clamped, full faced gaskets 14 distribute pressureacross the stack to seal gaskets 30 and masks 22, 24. The purpose ofgaskets 14 is also to provide a terminal seal between the internalfluids and the external atmosphere and to provide electrical isolationbetween first CCF 21 and first clamping plate 12 at one end of thefilter press assembly and between second CCF 21 and second clampingplate 34 at the other end of the assembled system 10. The purpose ofgaskets 14 is also to provide a means for sealing the periphery ofchamber 103 and channel defining apertures 98, 99, 100 and 101 of CCF's21 against the inner face of rigid plates 12 and 34.

Those skilled in the art will realize that the gaskets and masks asshown are non-limiting, and that additional masking may be provided toassist with material stability, engineering requirements, and protectionfrom corrosion. Gaskets (14, 30) and masks (22, 24) should be providedfrom a material that is electrically insulating, such as an elastomer,fluoropolymer, or thermoplastic, or combination thereof. In particularthey may be provided from a high-performance thermoplastic elastomer(such as Santoprene™), from EPDM (ethylene propylene diene monomer)rubber, from a polytetrafluoroethylene compound (such as Teflon™)polypropylene, polyethylene, or from a synthetic rubber andfluoropolymer elastomer compound (such as Viton® rubber).

To elaborate further on gaskets 30, such gaskets do not provide anycurrent carrying capabilities, or depth to the cell for productcirculation. For example, the ratio of CCF (20 or 21) depth 103A to thedepth of gasket 30 can be preferred as low as 1:1, however designs maypreferably increase CCF depth 103A to ratios in the range of 10:1 (whereCCF depth is 10 times the gasket depth), or to any ratio greater thanthis as best suited to the engineering requirements of theelectrochemical process.

Further, achieving depth for product circulation as part of the CCF (alow-cost metal conductor) is preferred economically to providing depththrough an insulating gasket material, particularly if the metal of theCCF has a lower cost than the insulating gasket material. It wouldfurther not be functional for insulating gaskets 30 to be increased indepth for the purpose of creating space for product circulation; as thecreated circulation space would be located between an electroactivestructure (26 or 102) and separator 28, which would negatively disruptthe hydrodynamics of product circulation. Therefore, a large ratiobetween CCF depth 103A and the depth of gaskets 30 is preferred asdescribed above, but non-limiting in view of other ratios which may beused.

The function of separators 28 is to divide the positive and negativeelectrochemical reaction regions, thereby separating the anolyte andcatholyte in all of the unipolar filter press stacks presentlydescribed. Separators 28 also provide a barrier which prevents orminimizes gases produced on the anodic electroactive structures and thecathodic electroactive structures to mix, while at the same timeallowing for ions in solution to pass through it. Separators 28 may beprovided from a diaphragm-type or membrane-type separator material asappropriate for the underlying electrochemical process. As non-limitingexamples, separator 28 may be provided from felt, porous polysulphone,polyphenyl sulphide, or another type of cation exchange or anionexchange membrane.

The purpose of the clamping plates 12 and 34 (as well as the equivalentplates 312, 334, 412, 434, and 512, 534 shown in other figures) is toprovide strong and rigid mechanical structures for applying the requiredsealing pressure on the gaskets and masks (14, 30, 22, 24) to seal theperiphery of the apertures, by means of an external filter pressclamping device.

The purpose of electroactive structures 102 (positive, anodic in thecase of electrolysis) is to provide an interface for electrons andreactants to electrochemically react on the conductive surface and forthe product to leave from the conductive surface. The purpose ofelectroactive structures 26 (negative, cathodic in the case ofelectrolysis) is to provide an interface for electrons and reactants toelectrochemically react on the conductive surface and for the product toleave from the conductive surface.

The separators 28 and electroactive structures 26 and 102 haveapproximately the same size and shape. The CCF's 20 and 21, the framegaskets 30, and gaskets 14 have approximately the same rectangulardimensions. When assembled, the outer peripheral edges of all thesecomponents are generally aligned. Electroactive structures 26 and 102and separators 28 are shorter than 20, 21, 30 and 14 so they do notencroach on any of the CCF apertures (52, 54, 80, and 24) which connectto transfer passageways.

Those skilled in the art of electrolysis will understand the circularityof the apertures in gaskets 14 and end plates 12 and 34 is non-limiting,and apertures of a variety of other generally rectangular, ovular, orpolyhedral shapes may be alternately employed. Further, the apertures inthe CCFs presently described are depicted as rectangular in the Figures,however those skilled in the art of electrolysis will understand theycould be provided in other shapes such as: square, ellipsoidal, oval, oranother polygon. The apertures may further have their cornerssubstantially rounded to avoid the creating stagnant flow regions whichmay cause corrosion or lower the throughput of gas product at sharpcrevices.

The purpose of outwardly extending tabs 64 (FIG. 3A) is to provide oneembodiment of the location in a filter press where electricalconnections are made, either to an adjacent unipolar filter press stack,to a power supply (power conditioning equipment), or to any other sourceof direct current electrical supply or generation to allow the flow ofcurrent to or from electroactive structures 26 and 102. Frame section 55of CCF 50 (FIG. 3A) is laterally thicker than its opposed frame section51, and includes one or more outwardly extending tabs 64 in oneembodiment. In another embodiment, in place of tabs 64, a hole or otherfeature may be provided such that an external bus bar clamp, or otherform of electrical connection, can be applied to form an electricalconnection with frame section 55.

The tabs for electrical connection 64 are preferably equidistantlyspaced, and are of a width approximately proportional to the CCF depth.Tabs 64 bring current linearly across the whole CCF, and providesufficient electrical contact between the CCF and the busbar connectingto the external power supply (one type of electrical connection). Thedimensions of the tabs for electrical connection 64 are non-limiting inthis disclosure.

In the case of the filter press stack 10, the electrical connection ismade by connecting one polarity of a power supply (generally DC current)and tabs 64 on one side of the filter press stack. The tabs 64 on theother side of the filter press stack are attached to the oppositepolarity of the power supply. The power supply polarities provided tothe tabs 64 define the polarities of the entire system (i.e. thepositive and negative symbols shown in FIG. 2 ). In a preferredembodiment, tabs 64 for electrical connection are provided withserrations 64A on one or more surfaces to improve the electricalconnection between the CCF and the power supply.

To create an electrolysis system that connects two filter press stacks10, the second filter press stack 10 would be located adjacent to thefirst in a manner such that their tabs for electrical connection 64 wereapproximately aligned facing each other, and that an electricalconnection between the two sets of tabs is made. The electricalconnection between the two sets of tabs 64 may be provided through avariety of methods, including but not limited to conductive bus bars andconductive wires. In this manner, the unipolar filter presses areconnected in series with each other, together creating an electrolysissystem of two filter press stacks. Additional filter press stacks 10 maycontinue to be added in this way to laterally expand the system.

The paragraphs following this relate to provisions for reactant andproduct circulation in a unipolar filter press electrolyser based onCCF's. Particularly the unipolar filter press assembly 10 shown in FIG.2 is referred to. However, the provisions for reactant and productcirculation described herein may be equivalently applied to theembodiments of FIG. 7 (310), FIG. 12 (410), and FIG. 14 (510) and theircorresponding reactant and product ports as described later on. Themethods may further be applied to any other CCF-based electrolyserembodiment. The discussion below is carried out using the example ofalkaline water electrolysis for ease of comprehension, however theprovisions for circulation discussed below may further be equivalentlyapplied to a unipolar filter press for chlorine electrolysis, or anyother process for which a unipolar filter press of CCF's are employed.

In one configuration, alkaline water electrolysis, the preferredorientation of the filter press has tall vertically oriented CCF's whichallow electrolytically produced hydrogen and oxygen gases to risevertically within the circulation chamber 103. Oxygen generated on theanodically polarized CCF's electroactive surfaces structures (asindicated by 102 in FIG. 2 ) will rise and cause gas-lift circulation ofthe anolyte and the oxygen gas mixture within the CCF's structure (andbetween the two electroactive surfaces of the same anodic potential).The anolyte and oxygen gas product will travel out of the CCFelectroactive area to the associated product removal channel throughpathways defined by gasket support pieces 56 and then via first transferpassageway 116 to a location where gas liquid separation and electrolyterecirculation into transfer passageway 117 can occur in end plate 34.

The cathodically polarized electroactive structures 26 will generatehydrogen gas. The hydrogen gas will provide a lifting means to move thecatholyte and hydrogen mixture up through the CCF's 21 through pathwaysdefined by gasket support pieces 56, and then via third transferpassageway 118 to a location where gas liquid separation and electrolyterecirculation into transfer passageway 119 can occur in end plate 12.

In an embodiment where it is preferable for internal gas/liquidcirculation to be provided in between end plates 12 and 34, twoadditional CCFs with no electroactive structures may be employed at anypoint in the stack; one to connect corresponding catholyte output/inputpassageways, and one to connect corresponding anolyte output/inputpassageways. These additional frames are referred to as “downwardcirculation frames,” as they circulate reacted electrolyte downwardswithin the stack from the output to the input product transferpassageway.

For example, a cathodic downward circulation frame may be applied inFIG. 2 (in addition to the required non-limiting gasket and mask partsto allow for proper sealing and insulation) to connect catholyte fromthe cathodic output passageway 118, such that it falls down through theforce of gravity into the cathodic input passageway 119, all withoutexiting the filter press. The cathodic gas would be separated from thecatholyte liquid in passageway 118, before the gas product passesthrough end plate 12 and exits the filter press. In addition to thecathodic downward circulation frame, an equivalent anodic downwardcirculation frame would further be required to equivalently connectanodic output passageway 116 to the anodic input passageway 117.

In place of using CCFs without electroactive structures as downwardcirculation frames, any other part that allows equivalent provisions fordownward circulation may be employed as downward circulation frames.Discharge and feed channels may further be provided at other locationswithin the filter press stack, with suitable equivalent product/reactantfeed/removal ports inserted therein.

Those skilled in the art will understand methods of adding feed water,cooling water, returning electrolyte from the external capture devices,provisions for gas liquid separation, and the creation of mixing zonesof the anolyte and catholyte to ensure the overall electrolyte hasminimal differential electrolyte concentration gradients. Thesenon-limiting methods may be applied to provide internal or externalcirculation.

Those skilled in the art will further understand methods of maintainingelevated absolute pressure within the mechanical capacity of the filterpress to withstand, as well as methods of controlling levels ofcatholyte and the anolyte in the circulation system and differentialpressures in the circulation system.

To provide further information on particularly useful features of theCCF in the optimization of filter press efficiency to its targetapplication, some additional details are provided. In summary, the CCFwidth (as represented by members 53, or 57, or 353 described later on),the height (as represented by members 51, or 55), and the depth(provided at circulation chamber, 103A) of all CCF embodiments presentlydescribed are parameters which can be selectively engineered, such thata given CCF embodiment is tailored to suit the engineering targets ofits application. In particular, the width, height, and depth parameterscan be tailored to meet a given cost target, an electroactive surfacearea target (for product generation space), a pressurization target,and/or an overall efficiency target. The ability to tailor theseparameters to the application's targets without technology-imposedconstraints or substantial incremental costs is a core advantage of theCCF design, as applied to create a unipolar filter press electrochemicalcell.

For example, pressure characteristics are best optimized by theembodiments of FIG. 4A and FIG. 6A, through customizing the quantity ofstruts in the design, defined respectively as 69 or 58 and discussedlater on. One of the purposes of the struts 69 and 58 is to providemechanical reinforcing strength to the CCF. The greater the number ofstruts for a fixed CCF height, the greater the CCF's ability to operateat elevated pressure, while still retaining its preferred rectangulargeometry. Furthermore, the height of the CCF can be continuouslyincreased while still retaining this preferred rectangular geometrythrough the provision of additional struts, as required to continuesupporting the CCF's mechanical integrity at the target pressure. Thepresence of struts 69 or 58 in a CCF further enables minimization of thelateral width of side members 51 and 55 (otherwise required at largerwidths for mechanical support), while still achieving a “rugged” designcapable of pressurization above atmospheric pressure.

In addition to the conducting struts enhancing mechanical strength,because they are made of the electrically conducting material of theframe itself, these struts also improve current conduction to theelectroactive surfaces through direct connection. In the preferredembodiment of FIG. 5A, conducting spears 76 are provided instead ofconducting struts, and will be described later on. Spears 76 provide analternative method to improve the electrical conductivity of the CCFthrough direct connection. The spears however do not contribute toreinforcing the mechanical integrity of the CCF for pressurization, asthe struts of the preferred embodiments of FIG. 4A and FIG. 6A do. As awhole, improvements to CCF conductivity through the provision of any ofthe additional conducting features (i.e. any described spears or struts)contributes to improving the overall efficiency of a unipolar filterpress device.

It is particularly of interest that the conducting features' height,width, and depth can be precisely adapted to further optimize currentconduction for a given CCF application. For example, by increasing thedepth of a conducting feature 69, 76 or 58 (achieved by increasing CCFdepth) while maintaining a fixed height and width of the feature, thecross-sectional area of the feature is increased. Increased crosssectional area of the conducting feature consequently improves currentconduction to the electroactive structure. It is possible to increasethe cross-sectional area of a conducting feature by increasing itsheight or width as well, however, this comes with the efficiency andcost trade-off of subtracting space from the available electroactivesurface area for product generation (i.e. total area of theelectroactive structure—surface area in direct contact via conductingfeature=practical available surface area for product generation). Byincreasing the CCF depth to improve conduction, rather than increasingthe height and width of the conducting features, improvements toconduction are achieved without subtracting any excess practical surfacearea for product generation.

The presence of additional conductive features within a CCF furtherenables the use of thinner electroactive structures, as compared to aCCF embodiment without any additional conductive features. The use ofthinner (and consequently less costly) electroactive structures isenabled as the added conductive features support a portion of thelateral current, conducting across the CCF over the electroactivestructures. Because the additional conductive features support lateralcurrent conduction, they further allow for a CCF laterally wider thanshown to be designed, such that the length of lateral cross members 53,57 is increased. It can be desirable to achieve a laterally wider CCFdesign to increase the practical product generating surface area of theCCF, as the electroactive structure applied to the widened CCF isproportionally wide. Therefore, a CCF with additional conductivefeatures may advantageously be modified in lateral width to achievelarge surface area targets at low incremental cost. Customization ofelectroactive surface area can further be provided by adjusting thevertical height of the CCF. The CCF design being substantiallyrectangular, vertical height expansion allows for an efficient use ofplant area. Preferably, the rectangular geometry of the CCF comprises aheight to width ratio in the range of 2:1 to 6:1, however this featureis non-limiting and may be adjusted to best suit the engineeringrequirements for the application of the device.

Finally, variations in electrolyte volume, gas and liquid velocity, aswell as the void fraction of electrolytic gases within circulationchamber 103 of any CCF embodiments presented in this disclosure can becontrolled in part by adjusting the CCF's depth.

Referring to FIG. 3A through 3D, preferred CCF 20 and CCF 21 embodimentsof FIG. 2 will be described in more detail. CCF 20 and CCF 21 areessentially identical except for the fact that they are of differentpolarity, depending on their position in the assembled electrolyser 10.They are not mechanically different. Subject to the CCF polarity andcorrosion processes, they may or may not be physically different fromeach other. For example, an anodically polarized CCF may require asurface treatment such as nickel plating or dimensionally stablematerials of construction as compared to a cathodically polarized CCF.

Each of CCF's 20 and 21 includes an electronically conductive frame 50having two side members 51 and 55 and two lateral cross members 53.Frame 50 is made from a conductive material suitable for the intendedapplication of CCF 20 and CCF 21 and may be made of carbon steel, nickelplated steel, titanium, nickel, carbon, and alloys. They may also beprovided with coatings known to those in the art that are resistant tothe corrosive effects of the environment in which the CCF 20 and CCF 21are to be placed. Non-limiting example environments in which CCF 20 andCCF 21 may be placed include, but are not limited to, sodium chloride,sodium hydroxide, potassium hydroxide, chlorine, hydrogen, oxygen,sodium hypochlorite, sodium chlorate and sulphuric acid. All of the CCFembodiments discussed in this disclosure may be provided from the samegroup of materials listed above.

Frame 50 and other variations of it are designed particularly tominimize the impact of corrosion. Crevices and stagnant areas wherecorrosion may occur are avoided where possible in the design. In thisand in all CCF embodiments presently disclosed, the presence of notches66 and 67 along the inner surface of the long frame members 51 and 55 isan optional beneficial provision to maximize the vertical length of thecirculation chamber (103) while defining the lateral width of theiradjacent aperture (52 or 80) consequently defining the lateral width ofthe product transfer passageway that passes through said aperture (52 or80). For example, the lateral width provided for product transferpassageways 116 and 118 in FIG. 2 would be impacted by the lateral widthof notch 66 into aperture 52, and the lateral width provided for producttransfer passageways 117 and 119 in FIG. 2 would be impacted by thelateral width of notch 67 into aperture 80. In one embodiment, thenotches 66 and 67 are sized to provide a similar cross-sectional area inthe adjacent apertures (52, 54 and 78, 80) after masks 22 and 24 areapplied, while maximizing available circulation chamber volume 103.

All CCFs presently disclosed are provided as one integral part, whichmay be manufactured through a variety of methods. These manufacturingmethods are non-limiting and may include any one or combination of:laser cutting, plasma cutting, water jet cutting, machining, sand orinvestment casting, or any other applicable manufacturing technology.

In an embodiment, any of the single CCFs presently described may beprovided with an additional channel in strut (or “arm”) 115 (orequivalently struts 360 and 315 for a double CCF, which bound catholyteand anolyte input passageways) such that anolyte and catholyte mixingmay occur between the associated transfer passageways feeding intocirculation chambers 103, to favourably adjust the concentrationgradient within the electrolyte. In embodiments where an aperture foranolyte and catholyte mixing upon input into the filter press isinserted (“mixing aperture”) in strut 115 (or equivalent struts boundingcatholyte/anolyte input passageways), an additional gasket support piece56 with channels may be provided to fit within the bounds of the mixingaperture. As described later, such a gasket support may be provided tobe friction fit in the mixing aperture, or in an alternate embodiment agasket support may be provided integrally of the CCF, with additionalthrough-channels provided to allow mixing.

FIG. 3B shows the preferred CCF embodiment 50 with electroactivestructures (equivalent to 102 or 106) attached. FIG. 3C shows a varietyof exemplary electrode structures 40, 41, 42, 43, 44 and 45, any ofwhich may be substituted equivalently for electrode structures 102 or 26provided in FIG. 2 .

The structures shown in FIG. 3C could be comprised of any solidconductor, either single metal, or alloy or a coated metal or alloy, andinclude: a planar sheet of circular perforations 40, sheet 41 being of aperforated sheet of continuous slots, sheet 42 being of a perforatedsheet of repeated slots, sheet 43 being of a sheet of hexagonalperforations, sheet 44 being an expanded metal sheet, and sheet 45 beinga woven mesh. Those skilled in the art of electrolysis will understandthat the electrode surface structure employed is non-limiting. Forexample, perforated sheets of other shapes or a metallic wool may alsobe employed as an electroactive structure. While some of the structuresshown in FIG. 3C are shown with some blank space to simplify theirvisualization, all structures are continuous.

All electroactive structures presently described are obviouslyperforated or otherwise “openworked” to permit the transport of theproducts or reactants between the separator 28 and the circulationchamber 103 as shown in FIG. 2 .

The diamond shaped apertures shown of electroactive structures 26 and102 of FIGS. 2 and 44 in FIG. 3B, and further electroactive structureaperture designs shown by 40, 41, 42, 43, 44 and 45 in FIG. 3C are forillustrative purposes only; such apertures can be of any configurationsuitable for the adequate operation of the electrochemical system atuse.

While any of the electrode structures 40 to 45 may be employed in any ofthe embodiments of the present disclosure, thick, mechanically robustembodiments of electroactive structures 40 to 45 are preferred with CCFembodiments such as frame 50 in FIGS. 3A and 3B that do not possessadditional features for electrical conduction and mechanical supportsuch as shown in FIGS. 4A to 6A, to provide additional rigidity andconduction capabilities. CCF embodiments which do possess additionalconductive and structural features may be provided with a thinnerelectroactive structure of comparatively lower electrical conductivity.

Electroactive structures may be attached through a variety ofmanufacturing methods. These manufacturing methods are non-limiting andmay include any one or combination of: press-fitting, spot welding,thermal welding, ultrasonic welding, electron beam welding, laser beamwelding, tungsten inert gas welding, or any other applicable technology.

Generally, in order to attach the electroactive structure to the CCF,welds would be performed on some or all the planar surfaces surroundingthe chamber 103, particularly on the sides of the frame. In embodimentsdescribed later on (FIG. 4B, FIG. 5B, FIG. 6B) with lateral struts orconductive structures welding may be additionally provided on thelateral struts or conductive structures. Generally, in all cases,electroactive structures are substantially flush with the outer surfacesof the CCF they are attached to.

If metallic wool were to be used as an electroactive structure, themanufacturing method of press-fitting would be the preferred method ofits attachment to the CCF. In a press fit, one may only need attachmentat a few (or no) uniquely dedicated locations, thus reducing theprecision required in assembly and the total assembly costs. In the“press-fit” embodiment using a CCF with lateral struts or conductivestructures (such as FIG. 4B, FIG. 5B, and FIG. 6B described later on),no welding would be required. In one embodiment of a press-fit,conductive struts 69, and 58, from FIGS. 4 and 6 described later aresqueezed against opposing struts in the next CCF, providing additionalsupport for the screen mechanically to improve electrical contact.

Frame 50 when used in CCF 20 is constructed such that it defines acirculation chamber 103 that is hydraulically connected to the channeldefining apertures 52 and 80 via channel defining gasket support pieces56 seen in FIG. 2 and FIG. 3A. Frame 50 when used in CCF 21 isconstructed such that it defines a circulation chamber 103 that ishydraulically connected to the channel defining apertures 99 and 100 viachannel defining gasket support pieces 56 non-specifically described butidentical to pieces 56 as mated to CCF 20 in FIG. 2 or CCF 50 in FIG. 3Aat the provided insertion points 56A. Gasket support pieces 56 arenon-limiting, and may further be substituted interchangeably for any ofgasket support pieces 120, 121, or 122 as shown in FIG. 3D or anyalternative gasket support piece serving the equivalent purposes of:controlling product and reactant passage through apertures 99 and 100 inCCF 21, controlling product and reactant passage through apertures 52and 80 in CCF 20, mechanically supporting first and second gaskets 30,ultimately mechanically supporting the integrity of transfer passageways116, 117, 118, and 119.

The gasket support pieces 56 can be used interchangeably with any of theCCF embodiments described in the figures. Gasket support pieces 56 (or120, 121, or 122) are preferably made from a metallic material, and maybe made of carbon steel, nickel plated steel, titanium, nickel, carbon,and alloys or coatings on substrates known to those in the art that areresistant to the corrosive effects of the environment in which the CCF20 and CCF 21 are to be placed. Gasket support pieces 56 mayalternatively be provided from polymeric, ceramic materials, or acombination of metallic, polymeric and ceramic materials that fulfil theequivalent purposes.

Gasket support piece 122 shows an embodiment in which a plurality ofholes are drilled through the member for liquid flow from chamber 103 upto the upper passageway. Gasket support member 121 is produced as a wavystructure while gasket support 120 has two slots located therein ratherthan a plurality of holes.

In one embodiment, gasket support pieces 56 may be provided from thesame unitary part as the CCF itself as shown in 56B in FIGS. 3F and 3G;such that an insertable electrically conductive strut withthrough-channels similar to cross strut 58 described later on isreceived where gasket support piece 56 is shown in the assembly of FIG.2 . In another embodiment, a non-removable gasket support piececomprising channels embedded therein may be provided as part of the CCFitself at any location where gasket support piece 56 is shown. Theselection of a removable or non-removable gasket support piece 56 isdependent on cost of manufacturing, and either gasket support pieceembodiment may apply to any single CCF or double CCF embodimentpresently described.

Alternative embodiments of integrally provided non-removable gasketsupport pieces with one or more through-channels configured to allowproducts and reactants to pass through it in operation, specificallysuch that gases and liquids may pass in a controlled manner betweencirculation chamber 103 and a product transfer passageway (such as116-120) are shown in FIG. 3F and FIG. 3G. Gasket support 56B is formedby means of subtractive manufacturing such that channels are providedtherein, and further, as with the other integral gasket supports, 56Bmay be integrally provided between any opposing L-shaped member and CCFside arm it is positioned between. The gasket support embodiment of 56Cis provided with one through-channel aperture for controlling gas/liquidflow based on the dimensions of the aperture. In embodiment 56D, agasket support and two adjacent apertures are created by extending anintegral part of the CCF's upper lateral cross member 57, thus dividingthe one aperture below it into two, and supporting adjacent gaskets bymeans of the general “T-shape.” Finally, in gasket support embodiments56E and 56F, two or more through-channels are provided in an integralhorizontal cross member by means of “negative T-shaped apertures.” Inthis configuration, the horizontal cross member gasket support isprovided with an extended vertical dimension, such that a portion of the“negative T-shape” therein allows liquids and gases to flow into theadjacent aperture (52). The integral horizontal cross member wouldcontinue to provide support for the adjacent gasket.

Those skilled in the art of electrolysis will further comprehend thatgasket support pieces applied at opposite ends of the CCF may bedifferent in size or structure.

In another embodiment, only one gasket support piece 56 is provided,between apertures 52 and 54 as shown in FIG. 3D, where reactedelectrolyte and gas output occurs in electrolysis. A gasket supportpiece on the opposite end between apertures 78 and 80 is optional inthis embodiment, as the control of liquid reactant entry into thechamber 103 may not require regulation by a gasket support piece in allcases. Equivalently, in double CCF embodiments described later on, theremay be provided gasket support pieces only where gas product output andreacted electrolyte output occurs, such that gasket support pieces whereliquid entry into circulation chambers 103 occur are optional.

In another embodiment, shown in FIG. 3E, modifications to the CCF 50 (orequivalently any other CCF described presently) are made to change thesize of the anodic and cathodic gas transfer passageways. Depending onthe electrolysis process, it may be preferable for the transferpassageway of one gas product to be greater in cross section (laterallyand/or vertically) than the other. When arm 114 is laterally equidistantbetween members 51 and 55, the space provided for adjacent transferpassageways is equal, and such a CCF may be utilized as an anode orcathode equivalently when configured in a filter press such as theexemplary filter press embodiment of FIG. 2 . CCF Figures provided inthis disclosure are generally made such that a CCF may be utilized as ananode or cathode equivalently for ease of comprehension, however thisdoes not limit other possibilities for CCF embodiments where CCF anodesand cathodes are distinct from one another.

For example, in another embodiment a CCF cathode is made substantiallyequivalent to frame 21 or 50, however additionally its arm 114 beingpositioned closer to frame member 55 than frame member 51, such thataperture 52 (and its associated product transfer passageway) isconsequently increased in lateral width while aperture 54 (and itsassociated product transfer passageway) and arm 63 are reduced inlateral width. In FIG. 3E this embodiment is shown as 50A. In thisembodiment, in order to assemble an exemplary filter press embodimentsubstantially equivalent to FIG. 2 , a complementary anodic CCFembodiment is made, 50B, its arm 114 being oppositely adjusted, suchthat aperture 52 (and its associated product transfer passageway) isconsequently reduced in lateral width while aperture 54 (and itsassociated product transfer passageway) and arm 63 are increased inlateral width. In another embodiment the opposite configuration isprovided, such that 50A is an anode and 50B is a cathode, such that thegas product passageway of the anodic product is increased in size andthe gas product passageway of the cathodic product is decreased in size.Alternatively, in another embodiment arm 115 is adjusted in height orlateral position such that the size of the passageways that feed intothe circulation chamber 103 are changed.

Such embodiments are particularly useful where the gas/liquid separationof one product (either anodic or cathodic) is achieved more readily thanthe other. For example, experimental data for alkaline waterelectrolysis has suggested the gas liquid separation of oxygen from theanolyte is provided more readily than the gas liquid separation ofhydrogen from the catholyte. Therefore, it may be beneficial to increasethe size of the cathodic product transfer passageway such that thehydrogen gas is allowed greater space in its transfer passageway.

To assemble a full filter press stack around CCF cathodes and anodeswherein the gas off-take transfer passageways are provided of differentsizes; all of the same parts (gaskets, masks, separators, gasketsupports) as previously described in FIG. 2 are provided as shown,however with corresponding adjustments as necessitated in shape andplacement adjacent to their designated CCF such that the stack isappropriately sealed. Any other CCF embodiment, such as double CCFembodiments or embodiments with additional product transfer passagewaysdescribed later in the present disclosure, may also be provided inalternative embodiments where anodic and cathodic transfer passagewaysare of differing sizes, thereby necessitating the size of aperturesintended for gas off-take be adjusted, along with the correspondingnon-limiting stack assembly components.

Slight modifications to the CCF may be optionally provided when requiredto improve the sealing of the assembly. The perimeter of circulationchamber 103 may be slightly recessed on one or more faces in order toensure the electroactive structures are substantially flush to thesurface of the CCF. Further, one or more continuous negative grooves mayadditionally be cut from both planar faces of any of the CCF embodimentspresently described. The negative grooves when applied are preferredaround the periphery of all apertures in the frame, such that gasket andmask components in the assembly are ensured to be flush to the surfaceof the CCF.

To provide further information on the applications for the CCFembodiments shown in FIG. 3A and FIG. 3B, some additional details areprovided. The CCF 50 as shown in FIG. 3A and FIG. 3B may be applied inany unipolar filter press electrochemical assembly (such as those asshown in FIG. 2 and FIG. 7 ), however it is particularly preferred in anarrow embodiment, for example where the lateral cross members 53 of theCCF is provided in approximately 8 inches or less, as dependent on theallowable resistive voltage loss through the electroactive structures44, and the current carrying capabilities of the electroactivestructures employed on the CCF.

As there are no additional conducting features provided in thisembodiment, the majority of the current carrying occurs across theelectrode structure alone, beginning on the left side adjacent to tabs64, then moving to the right (i.e. “parallel” to the electrode structureas is shown in FIG. 16A). A comparatively lower conductive loss wouldoccur with current travelling a shorter distance across the narrowembodiment, as supported by a robust, conductive electroactivestructure. This embodiment would also minimize manufacturing costs as noadditional conductive features or channels are required, and CCF weightwould be minimized.

This low-cost embodiment of FIG. 3A would be preferred for applicationsof electrolysis at low pressure and for small-scale production. It isnot the preferred embodiment for large scale alkaline water electrolysisin a unipolar filter press stack of high electrical efficiency operatingat high pressure, with large surface area to maximize product generationper CCF.

Large surface area per CCF (such that the lateral cross members 53, 57are approximately between 8 inches to 56 inches in length) is apreferred embodiment for an electrolyser applied to large scale alkalinewater electrolysis. Preferred CCF embodiments with additional conductivefeatures such as in FIG. 4A, FIG. 5A, FIG. 5C, and FIG. 6A are intendedfor alkaline water electrolyser systems requiring large surface area perCCF; to achieve the high DC electrical currents required for a largeproduction rate (e.g. approximately 1 kg to over 20 kg of hydrogenproduced per hour) within one unipolar filter press electrochemicalcell. Such embodiments are preferred for large surface area applicationsbecause of the benefits of the additional conductive features aspreviously described.

FIG. 4A shows an isometric view of a preferred embodiment, a unitary CCF68 similar to CCF 50 in FIG. 3A, which further includes cross strutmembers 69 that extend between elongate side frame members 51 and 55which are configured to be insertable for ease of manufacturing. Theends of struts 69 are enlarged with a bulbous shape giving the strut a“dog bone” structure, and frame sections 51 and 55 have correspondingvoids produced therein to receive the ends of the struts. Two crossstruts 69 are shown but it will be appreciated that there could only beone, or there could be more than two. The enlarged section of one end ofthe strut 69 in FIG. 4A shows a plurality of holes 70 formed along thelength of the strut which provide flow paths upwards through the strutduring electrolysis.

In another embodiment, after manufacturing the cross members 69 suchthat holes 70 are provided therein and cross members 69 are insertedinto CCF 68, cross members 69 are welded or otherwise electricallyjoined to frame member 55, which contains the tabs 64 for electricalconnection, thus improving the robustness of the electrical connectionprovided to cross members 69. Similarly, in a double CCF embodiment ofFIG. 9A described later on, cross members 69 may be electrically joinedto central frame member 332 to improve electrical connection to thecross members 69.

FIG. 4B shows the CCF 68 of FIG. 4A but with electroactive structures 44affixed to the CCF ready for insertion into the filter press stack.

FIG. 5A shows a preferred embodiment of a single CCF 74 which instead ofhaving struts fully extending between members 51 and 55, has integralconductive “spears” 76, extending partially across the width betweenframe members 51 and 55. The frame member 55 to which the spears 76 areintegrally provided is the side that accepts the most amperage in thedevice, being adjacent to the electrical input tabs 64 in FIG. 5A. Inthe case of double CCF 374 with spears, described later on in FIG. 10A,current travels laterally; entering one set of spears, travelling acrossthe central axis 332 of the double CCF, and then over to the next set ofspears. The benefit to this positioning is that during electrolysis,product generation would therefore be largely segregated to the areawhere there is the greatest amperage (i.e. where the spears areprovided). Gas evolution into the offtake transfer passageway could thenbe maximized where there is comparatively less amperage (and thereforeless “wasted” amperages by bubble travel).

In another embodiment, to improve the circulation of liquid electrolytesin chamber 103, one or more through-channels may be provided in thespears 76 (or 76A described later). Preferably, the one or more channelsare provided adjacent to frame member 55, the side the spears areprovided from, allowing improved circulation of electrolyte in theseregions. Similarly, in a double CCF embodiment of FIG. 10A describedlater on, spears 76 (or 76A) may have through-channels provided adjacentto central frame member 332.

In an alternate embodiment, one or more spears 76 or 76A may extendacross circulation chamber 103 to meet outer frame members 51, therebyforming an embodiment with both spears and one or more “conductivestruts.” Said one or more conductive struts may be provided in an theupward-pointing diagonal configuration of the spears, or in anothershape. In one embodiment the conductive strut may be substantiallyarcuate in shape, a beneficial shape to improve hydrodynamics in chamber103 discussed later. Said one or more conductive struts are beneficialfor improving the mechanical rigidity of this embodiment. Said one ormore conductive struts further comprise one or more through channelstherein, or they may be thinner than depth 103A, or have other meansprovided to support the circulation of gas and liquids within chamber103 towards off-take apertures while additionally supporting themechanical rigidity of the frame. Additionally, in any embodiment of aCCF with spears 76 (or 76A) the spears' dimensions may be different fromone another within the same CCF, such that a hydrodynamically beneficialgradient is created. Similarly, the double CCF embodiments describedlater on may employ any of the presently described features to createequivalent double CCF embodiments.

The embodiment of the CCF in FIG. 5A is advantageous economically ascompared to FIG. 6A as less milling would be required to createchannels, reducing the cost of manufacturing a CCF. During the plasmacutting (or equivalent cutting technique) of the CCF itself, the pathwould simply provide the spear structures 76 in an “upward-pointingdiagonal” arrangement integrally as part of the same CCF component. Theside of the CCF wherein the spears are not attached would provide aclear pathway for gas bubbles to ascend. In a preferred embodiment thespears 76 are angled upwardly as shown (but it is not essential) asbeing angled upwards encourages the flow of gas products to thecorresponding product transfer passageway (or “off-take passageway”) outof the filter press.

The preferred embodiment of FIG. 5A may be provided in an electrolyseroperating at pressures above atmospheric pressure, however as previouslydiscussed it may be preferred to employ an embodiment such as FIG. 4A orFIG. 6A with full struts 69 or 58 for pressurized operations, or anembodiment of FIG. 5A wherein at least one additional conductive strutis provided alongside spears 76.

FIG. 5B shows the CCF 74 of FIG. 5A but with electroactive structures 44affixed to the CCF ready for insertion into the filter press stack.

FIG. 5C shows another embodiment of CCF 74, shown as CCF 74A, withspears 76A. Studies have shown that providing spears such that they aresubstantially arcuate with an arcuately beveled tip provideshydrodynamic advantages in directing fluids and gases readily towardsproduct off-take passageways, at the greatest outlet velocity. However,differing tip shapes may be otherwise optimal as the CCF is applied todifferent electrolytic processes at different operating pressures.Spears 76A may have their tip shape and angle optimized to besubstantially arcuate and direct gas and fluids “upwards” towardsproduct offtake transfer passageways. Spears 76A may be provided withdifferent tip shape embodiments including but not limited to:continuously arcuate, planar, planar bevel, arcuately bevelled,polygonal, generally rounded, or any other appropriate shape.Preferably, the tips are made in an arcuately beveled embodiment.

In another embodiment, additional holes or “cut-outs” 79 of metal may beprovided from frame members 55, or 51 (or 332 of single or double CCFsdescribed later) where metal is not strictly required for currentconduction and mechanical support. Providing such cut-outs 79 enable areduction in part mass, increase scrap metal value, and support anincrease in lateral width of frame members 55 and 51 while minimizingpart mass. Extending the lateral width of frame members 55 and 51 allowsthe CCF to beneficially protrude externally to a filter press whenconfigured in a filter press electrolyser assembly embodiment such thatthe frame is air-cooled where it protrudes externally. Parts of the CCFprotruding from a filter press sealing profile with sites 79 inparticular protruding to additionally support air-cooling improvesfilter press heat removal capabilities. For the sole purposes ofair-cooling, however, cut-outs 79 are optional, and an embodiment of theCCF may be provided wherein parts of the CCF protrude from the filterpress sealing profile for air-cooling without any cut-outs 79. CCFs maybe adapted to increase heat removal from conduction, convection, orradiation. In another embodiment, lateral frame members 53 and 57 mayadditionally be increased in height with optional cut-outs provided forpurposes of air cooling the electrolyser, among other benefits. Cut-outs79 and/or protrusions for air-cooling may be further provided in anyother CCF embodiment presently described. In an alternative embodiment,cut-outs 79 may additionally be provided in other geometric shapes.

In another embodiment, outer frame members of the CCF may be adjusted inshape to further improve heat removal capabilities, for example beingcastellated, or otherwise bent or waved to create additional surfacearea and protrusions for air-cooling from the filter press.Additionally, coatings to further improve heat removal capabilities maybe applied to any CCF, discussed in detail later.

In another embodiment, central frame member 332 may be expanded inlateral width, such that additional material cut-outs 79 may beprovided, said cut-outs reducing part weight and increasing scrap metalvalue, and further creating further beneficial sites for air-cooling.

FIG. 6A shows another preferred embodiment, of a single CCF 85 which hasthe same basic structure as CCF 68 in FIG. 4A but instead of struts 69,it includes conducting struts or cross members 58 which are formed as aunitary single integrated piece with the frame members 51 and 55, sothat electricity is conducted through struts 58 to the electroactivestructures when the latter are electrically contacted to the struts 58and the CCF frame.

In operation, gas rises through struts 58 via channels 60 formed by thegaps between rectangular prisms (or equivalently “shapes”) 62 providedfrom the material of struts 58. The channels 60 provide space for thecirculation of electrochemical reactants and products within circulationchamber 103. While shapes 62 are shown for example as substantiallyrectangular prisms in FIG. 6A, they may be formed of any other suitableshape.

The shapes 62 on conductive struts 58 serve as attachment or contactingpoints to electroactive structures (such as 26 and 102 from FIG. 2 )that allow electrical conduction to and through the electroactivesurfaces during operation. These shapes 62 as illustrated in FIG. 6A areshown on only one side of the struts, however they can be located onboth sides of struts 58 where the attachment of electroactive structuresis required on both sides of the CCF.

The method to obtain the effect of a shapes 62 and the channels 60 fromstrut 58 could be via subtracting material from strut 58 throughmachining, stamping or another technique known to those skilled in theart of fabrication. While the channels 60 are shown as generallyrectangular in FIG. 6A, they may be alternately machined to resemble anyone or combination of a: “V” shape, “U” shape, trapezoid, semi-circle,or square. Shapes 62 may additionally be placed at any point along thestrut 58, and their positioning on different struts within the same CCFmay beneficially alternate to allow continuous upward circulation inchamber 103.

Alternately, in place of subtracting material to create the effect ofshapes 62, another embodiment possesses struts 58 which are entirelythinner in depth relative to the CCF sides 51, 55, 57 and 53 (“a thinconductive strut”), similar to how the strut 58 as shown in the Figureswould appear if the entire strut was reduced to the dimensions of 60shown in FIG. 6A, with no shapes 62. Circulation in chamber 103 wouldthen be provided around the thin conducting struts.

Said thin conductive struts (or “thin lateral cross members”) may beformed integrally of CCF 85, having their thickness subtracted by meansof manufacturing. Alternatively, thin conductive struts may beoriginally provided from a section of another plate having a thicknessless than a thickness of said CCF sides (51, 55, 57, and 53), but of thesame material as CCF frame 85, and consequently be joined between saidfirst and second side arms 51, 55 by means of a welding method such thatan electrical connection between the strut and the side frame members55, 51 is formed. The resulting embodiment of CCF 85 comprising thinconductive struts is substantially equivalent when produced by eithermethod described.

An alternate embodiment to this may have material added to the thinconductive struts to create the effect of raised shapes 62 and channels60.

FIG. 6B shows the CCF 85 with electroactive structures attachedcorresponding to embodiment 44 of FIG. 3C.

In an alternate embodiment, when one or more electroactive structures 44are provided on a single or double CCF embodiment comprising thinconductive struts, said electroactive structures may be further providedwith “indented inward-facing dimples” positioned directly facing andover top of the thin conductive struts, to allow for an electricalconnection to be made to the thin conductive struts, and to definechannels substantially parallel to frame members 55 and 51 (or 51 and332 in a double CCF with thin conductive struts) in the remaininglateral space between the thin conductive struts and the non-dimpledregions of the electroactive structure. These embodiments provideadvantages in reducing the complexity and cost of manufacturing CCF 85.In another embodiment, where recesses surrounding chamber 103 areadditionally provided as previously described, appropriate engineeringadjustments are made to allow the dimpled electroactive surface to beultimately substantially flush to the surfaces of the CCF it is appliedto.

FIG. 7 shows an isometric disassembled view of an electrolyser device310 built using a combination of four CCFs 50 (a “single CCF”)surrounding one CCF 350 (a “double CCF”). While single CCFs in the formof 50 are shown in FIG. 7 , any one or combination of single CCFs 68,74, or 85 may be substituted for any CCF 50 shown in FIG. 7 . Asdescribed, single CCF embodiments 68, 74, or 85 each hold uniqueadvantages for a given unipolar electrochemical device application, andwould be applied to best suit the intended application for theelectrolyser device 310. Similarly, any of double CCF embodiments 368,374, or 385 may be equivalently substituted for double CCF 350 in FIG. 7. The double CCFs described herein afford all of the same advantages ofthe single CCFs previously discussed, and further present a newadvantage of significantly reduced current path length and eliminationof the frequency of bus bar required between adjacent unipolar filterpress stacks, as will be discussed further. This yields a part countreduction and an installation and assembly labour reduction inmanufacturing the device. Any unlabeled parts in FIG. 7 have beenpreviously described for example separator 28, gaskets 30, gasketsupport pieces 56, circulation chambers 103, and electroactivestructures of opposing polarity 26 and 106.

The electrolyser device 310 comprises two unipolar filter press cells;the first unipolar filter press cell is provided with four producttransfer passageways 316, 317, 318, and 319. The second unipolar filterpress cell is provided also with four product transfer passageways, 320,321, 322, and 323. The products and reactants of the first and secondunipolar filter press cells are physically separated and do not mixwithin any of the end plates 312 and 334. The current generated by thepower input provided at tabs 64 of the single CCFs travels across thechambers of double CCF 350, as will be described later in FIG. 16 . Thisdesign allows electricity to be “bussed” centrally through the centralaxis of double CCF 350, represented by 322 in FIG. 8A, and distributedto the electroactive structures mounted over the circulation chambers103 provided on either side of the central axis 322 of double CCF 350.The only connection (electrical and physical) between the first andsecond unipolar filter press cells is the double CCF 350.

Moving from left to right, transfer passageway 316 is created by thechannel-forming combination of port 355 in first end clamping plate 312,and apertures 110, 54, 106, (as previously described) and aperture 352in double CCF 350. The side of CCF 350 which is joined to transferpassageway 316 is anodically polarized as indicated by the positive signin FIG. 7 . The polarizations shown in FIG. 7 are exemplary, and may bereversed in another embodiment. Transfer passageway 316 is fed withanodic product (a gaseous product in the example of the electrolysis ofwater) arising from the circulation chamber 103 of the right-hand sideof CCF 350, through a gasket support piece 56 into aperture 352 whichfeeds into passageway 316. Depending on the provisions applied forgas/liquid separation, which are non-limiting in this disclosure,anolyte liquid may also enter transfer passageway 316 with the anodicgas product. This anodic product gas and anolyte liquid is removed from316 for further processing through port 355 in first end plate 312.

Reading again from left to right, transfer passageway 317 is created bythe channel-forming combination of port 356 in first end plate 312(obscured by first right-hand gasket 14), and apertures 111, 78, 107,and aperture 380 in the anodically polarized side of CCF 350. The anodicproduct circulation chamber 103 of double CCF 350 is fed with anolyteliquid through aperture 380 and its corresponding gasket support piece.Anolyte reactant liquid is initially fed into passageway 317 throughobscured port 356 in first end plate 312. The anolyte liquid input intotransfer passageway 317 may be virgin electrolyte, or it may be recycledanolyte that has been removed from passageway 316 or 322 and externallyprocessed.

Reading from right to left, transfer passageway 318 is created by thechannel-forming combination of port 351 in first end plate 334, andapertures 94, 52, 90, 354 of double CCF 350, 90 and 52. The cathodicallypolarized CCFs 50 feed gaseous cathodic product through a gasket supportpiece 56 and into aperture 52 which then feeds into transfer passageway318. As noted equivalently for the anodic gaseous product, depending onthe provisions employed for gas/liquid separation in the filter pressstack some catholyte liquid may enter passageway 318 with the gaseouscathodic product. The product and any residual catholyte is removed atport 351.

Reading from right to left, transfer passageway 319 is created by thechannel-forming combination of port 353 in first end clamping plate 334,and apertures 109, 80, 108, 378, 108, 80. The cathodic productcirculation chambers 103 of CCFs 50 are fed with catholyte liquidthrough apertures 80 and their corresponding gasket support pieces.Catholyte reactant liquid is initially fed into passageway 319 throughport 353 in first end plate 334. The catholyte liquid input intotransfer passageway 319 may be water, or it may be recycled catholytethat has been removed from passageway 318 or 320 and externallyprocessed.

Reading from right to left, transfer passageway 320 is created by thechannel-forming combination of port 348 connecting to second end plate334, and apertures 94 (not shown due to cutaway), 54, 90, 356 of doubleCCF 350. The cathodically polarized portion of double CCF 350 feedsgaseous cathodic product from its cathodic chamber 103 up through agasket support piece 56 into aperture 356 which then feeds into transferpassageway 320. Depending on the provisions employed for gas/liquidseparation in the filter press stack some catholyte liquid may enterpassageway 320 with the gaseous cathodic product. The gaseous cathodeproduct and any residual catholyte is removed at port 348.

Reading from right to left, transfer passageway 321 is created by thechannel-forming combination of port 357 in second end plate 334, andapertures 109, 78, 108, and 381. The cathodic product circulationchamber 103 of CCF 350 is fed with catholyte liquid through apertures381 and its corresponding gasket support piece. Catholyte reactantliquid is initially fed into passageway 321 through port 357 in secondend plate 334. The catholyte liquid input into transfer passageway 321may be water, or it may be recycled catholyte that has been removed frompassageway 320 or 318 and externally processed.

Reading from left to right, transfer passageway 322 is created by thechannel-forming combination of port 349 in second end plate 312, andaperture 110, 52, 106, 355 in double CCF 350, 106, and terminates atsecond aperture 52. The CCFs 50 joined to transfer passageway 322 areanodically polarized. Transfer passageway 322 is fed with anodic gaseousproduct that arises from the circulation chamber 103 of anodic CCFs 50through gasket support pieces 56 and into apertures 52, which then feedinto passageway 322. Depending on the provisions applied for gas/liquidseparation anolyte liquid may also enter transfer passageway 322 withthe anodic gas product. This anodic product gas and anolyte liquid isremoved from 322 for further processing through port 349 in second endplate 312.

Reading from left to right, transfer passageway 323 is created by thechannel-forming combination of port 359 in second end plate 312, andapertures 111, 80, 107, 379, 107, and 80. The anodic product circulationchamber 103 of single CCFs 50 is fed with anolyte liquid throughaperture 80 and its corresponding gasket support piece. Anolyte reactantliquid is initially fed into passageway 323 through port 359 in secondend plate 312. The anolyte liquid input into transfer passageway 323 maybe virgin electrolyte, or it may be recycled anolyte that has beenremoved from passageway 316 or 322 and externally processed.

FIG. 8A shows an embodiment of a double CCF at 350 which includes acentral frame member 332 which extends between the lateral sections 353of the CCF. CCF 350 acts as a current bus between two adjacent unipolarfilter press cells. No tabs (such as tabs 64 in FIG. 3A) for electricalconnection are required on double CCFs for this reason. Double plate CCF350 can also be used to create multi-stack CCFs of greater than two (2)electrochemical unipolar filter press cell stacks, see FIG. 16C andassociated discussion.

This double plate CCF 350, where one half is the anode of one unipolarfilter press cell stack, and one half is a cathode in the adjacentunipolar filter press cell stack. By eliminating the need for a bus barbetween adjacent unipolar filter press cell stacks, the metallicresistive losses between the stacks are reduced, and the unipolar stackscan approach the low resistive losses achieved by state-of-the-artbipolar filter press stacks. The reduced current path length is a resultof the ability for the double CCF to act as an improved inter-cellelectrical connection (improving over an inter-cell bus bar) between twounipolar filter press stacks. The improvement comes from the feature ofthe double CCF that current travels only laterally between the adjacentcells, rather than both laterally and vertically as required on singleCCFs with tabs 64. It can also be more efficient in manufacturing to cutone large component rather than two small components to accomplish thesame task.

FIG. 8B shows CCF 350 of FIG. 8A but now with electroactive structures44 on opposing sides of the CCF.

FIG. 9A shows a double CCF embodiment 368 with the dog-bone shapedstruts 69 essentially the same as in the single CCF 68 of FIG. 4A butnow separate struts 69 are provided in both chambers 103 and providesame benefits as the single CCF 68.

FIG. 9B shows CCF 368 of FIG. 9A but now with electroactive structures44 on opposing sides of the CCF.

FIG. 10A shows a double CCF embodiment 374 with the spears 76 similar tothe single CCF of FIG. 5A but it is noted that the spears are integrallyformed with the central frame member 332 and project into the chambers103. FIG. 10B shows CCF 374 of FIG. 10A but now with electroactivestructures 44 on opposing sides of the CCF. The current from the doubleCCFs transfers laterally through the central frame member 332 from thespears of one unipolar filter press cell stack to the spears of theadjacent cell stack. Hence, “spears” extend from this frame member 332,such that current can travel laterally through the double CCF. Thesespears 76 provide same benefits as in the single CCF 74.

FIG. 10C shows a double CCF embodiment 374A with spears 76A, similar tothe single CCF of FIG. 5C, and the double CCF of FIG. 10A. CCF 374Afurther possesses cut-outs 79 as previously discussed. Consequently, thedouble CCF embodiment shown in FIG. 10C benefits from the previouslydescribed advantages of both the CCF of FIG. 5C and the double CCF ofFIG. 10A. The central axis 332 of any Double CCF embodiment presentlydescribed may be increased in lateral width to allow additional cut-outs79 to be made, further improving the heat transfer capabilities of theCCF.

Further, in another embodiment, a coating to improve heat removalcapabilities may be additionally applied to frame members of the doubleCCF, preferably to central frame member 332. The coating to improve heatremoval capabilities may be comprised of but is not limited to: highemissivity paint, ceramic-based or silicone-ceramic-based coatings,black pigmented coating, for example Aremco's 840-MS. In alternativeembodiments, coatings to improve heat removal capabilities of a CCF maybe applied to any CCF embodiment presently described.

Further, in another embodiment additional material shapes may beprovided to CCF frame members to increase the frame surface areaprotruding from the filter press such that heat transfer is improved.Such additional protruding material shapes may preferably be provided asfins, or another heat transferable shape.

FIG. 11A shows the double CCF at 385 which is the double CCF version ofCCF 85 in FIG. 6A. FIG. 11B shows the CCF 385 with the electroactivestructures 44 affixed thereto. The struts 58 have the same structure asin the single CCF 85 and provide the same benefits.

FIG. 12 shows an isometric disassembled view of a unipolar electrolyserdevice 410 built using single CCFs 450 wherein additional apertures forproduct transfer are provided. Any unlabeled parts in FIG. 12 aredescribed later, or have been previously described for exampleseparators 28, gasket support pieces 56, circulation chambers 103, andelectroactive structures of opposing polarity 26 and 102. Gaskets 414and 430 and masks 422 and 424 serve the same purposes as previouslydescribed gaskets 14 and 30 and masks 22 and 24 and end plates 412 and434, however they are provided in FIG. 12 and FIG. 14 withaccommodations for the additional product transfer passageways.

While single CCFs 450 are shown to have a bare product circulationchamber 103 analogous to single CCFs 50, their product circulationchamber 103 may be configured in preferred embodiments that include theconductive features of previously described single CCFs 68, 74, or 85,such that the CCFs of FIG. 12 with additional apertures for producttransfer may additionally have conducting struts (68, 85) or spears 76provided across their product circulation chamber. Similarly, theconducting struts or spears of previously described double CCFs 368,374, or 385 may be applied to the double CCFs 550 with additionalpassageways as shown in FIG. 14 . However, the CCF embodimentscontaining additional apertures for product transfer in FIG. 12 and FIG.14 cannot be equivalently substituted into the devices of FIG. 2 andFIG. 7 without additionally accommodating changes to the entireconfiguration such that FIG. 12 and FIG. 14 are effectively recreated.

The unipolar electrochemical device in 410 is comprised of one unipolarfilter press cell, with six product transfer passageways 416, 417, 418,419, 420, 421.

Moving from left to right, transfer passageway 416 is created by thechannel-forming combination of port 449 in end clamping plate 412, andapertures 494 in gasket 414, 493 in CCF 450, 460 in gasket 430, 488 inCCF 450, 460, and 493. The CCFs 450 which physically join to transferpassageway 416 are anodically polarized as indicated by the positivesign in FIG. 12 . The polarizations shown in FIG. 12 are exemplary, andmay be reversed in another embodiment. Transfer passageway 416 is fedwith anodic product (a gaseous product in the case of the electrolysisof water or chlorine electrolysis) arising from the circulation chamber103 of CCFs 450 joined to passageway 416, through a gasket support piece56 into aperture 493 which feeds into passageway 416.

Moving from left to right, transfer passageway 417 is created by thechannel-forming combination of port 459 in end plate 412, and apertures495, 480, 461, 478, 461, 480. The anodic product circulation chamber 103of CCFs 450 which physically join to transfer passageway 417 is fed withanolyte liquid through aperture 480 and its corresponding gasket supportpiece. Anolyte reactant liquid is initially fed into passageway 417through port 459 in end plate 412. The anolyte liquid input intotransfer passageway 417 may be virgin electrolyte, or it may be recycledanolyte that has been removed from passageway 418 and externallyprocessed.

Reading from left to right, transfer passageway 418 is created by thechannel-forming combination of port 452 in end plate 412, and apertures496, 492, 462, 489, 462, and 492. The anodic product circulation chamber103 of CCFs 450 which physically join to transfer passageway 418 isoriginally fed with anolyte liquid from transfer passageway 417 upthrough aperture 480 and its corresponding gasket support piece. Anodicgaseous product is generated in product circulation chamber 103 andflows into aperture 493 to enter transfer passageway 416. Surplusreacted liquid anolyte additionally flows into aperture 493, howeverthen passes through channel 483 into adjacent aperture 492 (as shown inFIG. 13A) ultimately entering product transfer passageway 418, where itwill be removed at port 452 in end plate 412. The reacted anolyteremoved from port 452 may be enriched as is done in chlorineelectrolysis to enrich depleted brine before it is recirculated backinto the system.

Reading from right to left, transfer passageway 419 is created by thechannel-forming combination of port 457 in end plate 434, and apertures495, 478, 463, 480, 463, 480. The cathodic product circulation chamber103 of CCF 450, indicated by the negative sign, which physically joinsto transfer passageway 419 is fed with catholyte liquid through aperture480 and its corresponding gasket support piece. Catholyte reactantliquid is initially fed into passageway 419 through port 457 in endplate 434. The catholyte liquid input into transfer passageway 419 maybe virgin electrolyte, water, or recycled catholyte that has beenremoved from passageway 420 and externally processed.

Reading from right to left, transfer passageway 420 is created by thechannel-forming combination of port 451 in end plate 434, 496, 489, 464,and 492. The cathodic product circulation chamber 103 of CCF 450 thatphysically joins to transfer passageway 420 is originally fed withcatholyte liquid from transfer passageway 419 up through aperture 480and its corresponding gasket support piece. Cathodic gaseous product isgenerated in product circulation chamber 103 and flows into aperture 493to enter transfer passageway 421. Surplus reacted liquid catholyteadditionally flows into aperture 493, however then passes throughchannel 483 into adjacent aperture 492 (as shown in FIG. 13A) ultimatelyentering product transfer passageway 420, where it will be removed atport 451 in end plate 434. The reacted catholyte removed from port 451may be processed externally as a final product, or recirculated backinto the system through passageway 419.

Reading from right to left, transfer passageway 421 is created by thechannel-forming combination of port 448 in end clamping plate 434, andapertures 494, 488, 465, 493. The CCF 450 which physically joins totransfer passageway 421 is cathodically polarized as indicated by thenegative sign in FIG. 12 . Transfer passageway 421 is fed with cathodicproduct (a gaseous product in the case of the electrolysis of water orchorine electrolysis) arising from the circulation chamber 103 ofcathodic CCF 450 joined to passageway 421, through a gasket supportpiece 56 into aperture 493 which feeds into passageway 421.

FIG. 13A shows a single CCF 450 with two apertures 478 and 480 at thelower or bottom part of the CCF and multiple apertures 488, 489, 492 and493 defined in the upper or top portion of the CCF 450. A gap or opening483 in strut 487 allows liquid electrolyte from aperture 493 to flowinto 492 during operation. This channel allows the reacted electrolyteto be separated from the gaseous product that will enter aperture 493,such that two separate adjacent product transfer passageways for reactedelectrolyte and gaseous product may be provided.

FIG. 13B shows CCF 450 now with electroactive structure 44 affixedthereto.

FIG. 14 shows an isometric disassembled view of an electrolyser device510 built using a combination of four single CCFs 450 surrounding onedouble CCF 550. Any unlabeled parts in FIG. 14 have been previouslydescribed for example separator 28, gaskets 414, 430, gasket supportpieces 56, circulation chambers 103, and electroactive structures ofopposing polarity 26 and 106.

The electrolyser device 510 comprises two unipolar filter press cells;the first unipolar filter press cell is provided with six producttransfer passageways 516, 517, 518, 519, 520, 521. The second unipolarfilter press cell is provided also with six product transferpassageways, 522, 523, 524, 525, 526, and 527. The products andreactants of the first and second unipolar filter press cells arephysically separated and do not mix within any of end plates 512 and534. The current generated by the power input provided at tabs 64 of thesingle CCFs travels across the chambers of double CCF 550, as will bedescribed later in FIG. 16 . This design allows electricity to be“bussed” centrally through the central axis of double CCF 550,represented by 322 in FIG. 15A, and distributed to the electroactivestructures mounted over the circulation chambers 103 provided on eitherside of the central axis 322 of double CCF 550. The only connectionbetween the first and second unipolar filter press cells is the doubleCCF 550.

Moving from left to right, transfer passageway 516 is created by thechannel-forming combination of port 549 in first end clamping plate 512,and apertures 494, 488, 460, 593 in double CCF 550. The side of CCF 550in which is joined to transfer passageway 516 is anodically polarized asindicated by the positive sign in FIG. 14 . The polarizations shown inFIG. 14 are exemplary, and may be reversed in another embodiment.Transfer passageway 516 is fed with anodic product (a gaseous product inthe case of the electrolysis of water or chlorine electrolysis) arisingfrom the circulation chamber 103 of the right-hand side of CCF 550,through a gasket support piece 56 into aperture 593 which feeds intopassageway 516. This anodic product gas and any residual anolyte liquid(if any) is removed from 516 for further processing through tubular port549 in first end plate 512.

Reading from left to right, transfer passageway 517 is created by thechannel-forming combination of port 559 in first end plate 512 (obscuredby first right-hand gasket 414), 495, 478, 461 (obscured byelectroactive structure), and 580 in the anodically polarized side ofCCF 550. The anodic product circulation chamber 103 of double CCF 550 isfed with anolyte liquid through aperture 580 and its correspondinggasket support piece. Anolyte reactant liquid is initially fed intopassageway 517 through obscured port 559 in first end plate 512. Theanolyte liquid input into transfer passageway 517 may be virginelectrolyte, or it may be recycled anolyte that has been removed frompassageway 518 or 526 and externally processed.

Reading from left to right, transfer passageway 518 is created by thechannel-forming combination of port 555 in first end plate 512, andapertures 496, 489, 462, 592. The anodic product circulation chamber 103of CCFs 550 which physically joins to transfer passageway 518 isoriginally fed with anolyte liquid from transfer passageway 517 upthrough aperture 580 and its corresponding gasket support piece. Anodicgaseous product is generated in product circulation chamber 103 andflows into aperture 593 to enter transfer passageway 516. Surplusreacted liquid anolyte additionally flows into aperture 593, howeverthen passes through channel 583 into adjacent aperture 592 (as shown inFIG. 15A) ultimately entering product transfer passageway 518, where itwill be removed at port 555 in first end plate 512. The reacted anolyteremoved from port 555 may be enriched as is done in chlorineelectrolysis to enrich depleted brine before it is recirculated backinto the system.

Reading from right to left, transfer passageway 519 is created by thechannel-forming combination of port 553 in first end plate 534, obscuredaperture 495 in gasket 414, 480, 463, 578, 463, and 480. The cathodicproduct circulation chambers 103 of cathodic single CCFs 450 are fedwith catholyte liquid through apertures 480 and their correspondinggasket support pieces. Catholyte reactant liquid is initially fed intopassageway 519 through port 553 in first end plate 534. The catholyteliquid input into transfer passageway 519 may be water, or it may berecycled catholyte that has been removed from passageway 520 or 524 andexternally processed.

Reading from right to left, transfer passageway 520 is created by thechannel-forming combination of port 554 in first end plate 534, 496,492, 464, 589, 464, 492. The cathodic product circulation chamber 103 ofsingle CCFs 450 that physically join to transfer passageway 520 isoriginally fed with catholyte liquid from transfer passageway 519 upthrough aperture 480 and its corresponding gasket support piece.Cathodic gaseous product is generated in product circulation chamber 103and flows into aperture 493 to enter transfer passageway 521. Surplusreacted liquid catholyte additionally flows into aperture 493, howeverthen passes through channel 483 into adjacent aperture 492 (as shown inFIG. 13A) ultimately entering product transfer passageway 520, where itwill be removed at port 554 in first end plate 534. The reactedcatholyte removed from port 554 may be processed externally as a finalproduct, or recirculated back into the system through passageway 519 or523.

Reading from right to left transfer passageway 521 is created by thechannel-forming combination of port 552 in first end plate 534, andapertures 494, 493, 465, 588, 465, and 493. The cathodically polarizedCCFs 450 feed gaseous cathodic product through a gasket support piece 56and into aperture 493 which then feeds into transfer passageway 521. Theproduct and residual catholyte (if any) is removed at port 552.

Reading from right to left, transfer passageway 522 is created by thechannel-forming combination of port 548 in second end plate 534, andapertures 494, 488, 465, and 573. The cathodically polarized portion ofdouble CCF 550 feeds gaseous cathodic product from its cathodic chamber103 up through a gasket support piece 56 into aperture 573 which thenfeeds into transfer passageway 522. The gaseous cathode product and anyresidual catholyte (if any) is removed at port 548.

Reading from right to left, transfer passageway 523 is created by thechannel-forming combination of port 557 in second end plate 534, andapertures 495, 478, 463, and 560. The cathodic product circulationchamber 103 of the cathodic portion of double CCF 550 is fed withcatholyte liquid through aperture 560 and the corresponding gasketsupport piece. Catholyte reactant liquid is initially fed intopassageway 523 through port 557 in second end plate 534. The catholyteliquid input into transfer passageway 523 may be water, or it may berecycled catholyte that has been removed from passageway 520 or 524 andexternally processed.

Reading from right to left, transfer passageway 524 is created by thechannel-forming combination of port 551 in second end plate 534, andapertures 496, 489, 464, and 572. The cathodic product circulationchamber 103 of double CCF 550 that physically joins to transferpassageway 524 is originally fed with catholyte liquid from transferpassageway 523 up through aperture 560 and its corresponding gasketsupport piece. Cathodic gaseous product is generated in productcirculation chamber 103 and flows into aperture 573 to enter transferpassageway 522. Surplus reacted liquid catholyte additionally flows intoaperture 573, however then passes through channel 563 into adjacentaperture 572 (as shown in FIG. 15A) ultimately entering product transferpassageway 524, where it will be removed at port 551 in second end plate534. The reacted catholyte removed from port 551 may be processedexternally as a final product, or recirculated back into the systemthrough passageway 519 or 523.

Reading from left to right, transfer passageway 525 is created by thechannel-forming combination of port 556 in second end plate 512, andapertures 495, 480, 461, 558, 461, 480. The anodic product circulationchambers 103 of anodic single CCFs 450 are fed with anolyte liquidthrough apertures 480 and their corresponding gasket support pieces.Anolyte reactant liquid is initially fed into passageway 525 throughport 556 in second end plate 512. The catholyte liquid input intotransfer passageway 525 may be virgin electrolyte or it may be recycledanolyte that has been removed from passageway 526 or 518 and externallyprocessed.

Reading from left to right, transfer passageway 526 is created by thechannel-forming combination of port 546 in second end plate 512, 496,492, 462, 569, 462, and 492. The anodic product circulation chamber 103of single CCFs 450 which physically join to transfer passageway 526 isoriginally fed with anolyte liquid from transfer passageway 525 upthrough aperture 480 and its corresponding gasket support piece. Anodicgaseous product is generated in product circulation chamber 103 andflows into aperture 493 to enter transfer passageway 527. Surplusreacted liquid anolyte additionally flows into aperture 493, howeverthen passes through channel 483 into adjacent aperture 492 (as shown inFIG. 13A) ultimately entering product transfer passageway 526, where itwill be removed at port 546 in second end plate 512. The reacted anolyteremoved from port 546 may be enriched as is done in chlorineelectrolysis to enrich depleted brine before it is recirculated backinto the system through ports 556 or 559.

Reading left to right, transfer passageway 527 is created by the channelforming combination of port 547 in second end clamping plate 512, andapertures 494, 493, 460, 568, 460, 493. The single CCFs 450 which arejoined to transfer passageway 527 are anodically polarized. Transferpassageway 527 is fed with anodic product (a gaseous product in the caseof the electrolysis of water or chlorine electrolysis) arising from thecirculation chamber 103 of single CCFs 450, through a gasket supportpiece 56 into aperture 493 which feeds into passageway 526. This anodicproduct gas and residual anolyte liquid (if any) is removed from 527 forfurther processing through tubular port 547 in second end plate 512.

The embodiments of FIG. 12 and FIG. 14 are particularly preferred forchlorine electrolysis in view of the additional product transferpassageways efficiently separating gaseous product from liquid reactedanolyte and catholyte. The additional separation of reacted anolyte andcatholyte from the gaseous product outputs is particularly preferred inchlorine electrolysis, as the reacted catholyte (sodium hydroxide) isdesired as an independent product, which can be externally diluted andpumped back into the catholyte input where more sodium hydroxide isproduced.

The embodiments of FIG. 12 and FIG. 14 are also preferred for alkalinewater electrolysis. As in all potential applications for this unipolarfilter press electrolyser embodiment, the additional transferpassageways provided allow the designer of the electrolyser additionalflexibility in how to operate and control it, and in how to process andmanage reacted electrolyte. As previously discussed, two downwardcirculation frames (one anodic, one cathodic) may be provided in theembodiments of FIG. 12 and FIG. 14 to facilitate internal recirculationof reacted electrolyte from the appropriate exit pathway into theappropriate entrance pathway.

FIG. 15A shows the double CCF 550 embodiment of the single CCF 450 ofFIG. 13A in which the upper and lower passageways on either side ofcentral frame member 332 are mirror images of each other. FIG. 15B showsCCF 550 with electroactive structures 44 affixed thereto.

In other embodiments of CCFs with additional transfer passageways (i.e.greater than the 4 transfer passageways per unipolar electrochemicalcell press shown in FIG. 2 and FIG. 7 ), different quantities ofadditional transfer passageways than shown in FIGURE's 13 through 15 maybe provided as necessitated by the application.

For example, one embodiment comprises a single CCF similar to FIG. 13Awherein arm 486 is removed, thus merging apertures 492 and 489 to createone aperture. When applied to form a single filter press electrochemicalcell, as in FIG. 12 , the catholyte and anolyte would mix when exitingthe frames of this embodiment, when placed where CCF 450 is shown. Aspreviously discussed, mixing anolyte and catholyte can be beneficial inalkaline water electrolysis to restore the desired electrolyteconcentration.

Similarly, another exemplary embodiment comprises a double CCF similarto FIG. 15A wherein arms 586 and 566 are removed to achieve theequivalent effect of anolyte and catholyte mixing when exiting thecirculation chamber 103. A CCF may be designed with other quantities oftransfer passageways should it suit the underlying electrochemicalprocess.

It is noted that any embodiments of any of the conductive featurespresently described (conductive struts, spears, thin conductive struts,arcuate conductive struts, etc.) may be combined within the circulationchamber of one CCF. For example, one CCF (either single or double) maybe provided with both spears and a conductive strut, or multipleconductive struts and one spear. Any other combination of the conductivefeatures presently described may be further employed. Further, any suchembodiments may include: any form of one or more through-channels withinsaid conductive features to allow the passage of fluids, said conductivefeatures may be reduced in thickness as compared to depth 103A at anyposition on the feature to allow the passage of fluids, said conductivefeature may be angled upwards or downwards or adjusted otherwise at anybeneficial orientation or shape for hydrodynamic flow, or provided in anembodiment with any combination of the above. The ability to achievelow-incremental cost customization of features to suit the conditions ofthe environment of the CCF is a key aspect of the present disclosure.

Additionally, CCFs employed within a given filter press need not beidentical. For example, a given filter press stack of CCFs may includeCCF embodiments provided with no features in their circulation chamber,spears, or conductive struts, or combinations thereof, all presentwithin the same stack. Further, the shape of the CCF frame may beadjusted such that corners of the external frame and/or aperturestherein are rounded, or otherwise adjusted in shape.

Beyond the preferred applications of alkaline water electrolysis andchlorine electrolysis, there are many other possible electrochemicalprocesses for which a unipolar filter press electrochemical device basedon the various CCF embodiments disclosed herein could be employed.

While the present CCFs can be used to create an electrochemical devicebased on entirely CCF-type current carriers and frames, as discussedthroughout the present disclosure, a CCF may also be adapted to suitother electrochemical devices which require replacement parts.

Combined Single-Double CCF System Expanded to Scale

FIG. 16A shows a simplified top-down view of the innermost components ofthe unipolar filter press electrochemical device of FIG. 2 (theinnermost components of FIG. 12 would also behave equivalently from thisview) and the consequent path of electrical current upon the innermostcomponents and their electroactive structures, illustrating inparticular the current travelling parallel to, and within theelectrically conductive product-generating electroactive structures. InFIG. 16A current enters the device from the left-hand side (indicated bythe + symbol), travels through the middle metallic current carrier frame20 to the attached conductive electroactive structures 102 on eitherface of the central unipolar CCF 20. The arrows provided onelectroactive structures 102 represent the path of current through thedevice, which runs parallel across the electroactive structure from“left” where the power input is presented to the “right.” Currenttravels through separator 28 in the form of charged ions. The separator28 is depicted as being compressed into the central aperture of gasket30 in FIG. 16 rather than being shown in the disassembled form of theprevious assembly figures. The outer two (2) cathodic CCFs 21 correspondto CCFs 21 as shown and described in FIG. 2 with conductiveelectroactive structures 26 attached. The filter press stack assemblydepicted in FIG. 16A is shown with three (3) CCFs but it will beunderstood that this filter press configuration using single CCFs can bescaled up in the longitudinal direction simply by inserting as manyunipolar CCFs similar to CCF 20 of alternating polarity between the twoCCFs 21 located at the ends of the stack with these additional CCFshaving electroactive structures 102 or 26 (+ or − depending on thepolarity) affixed to opposing sides of the CCF, as shown in the middleCCF in FIG. 16A.

FIG. 16B shows a simplified top-down view of the innermost components ofthe unipolar filter press electrochemical device shown in FIG. 7 (theinnermost components of FIG. 14 would also behave equivalently from thisview) and the consequent path of current upon the innermost componentsand their electroactive structures, illustrating in particular thecurrent travelling parallel to the product-generating electroactivestructures. Similarly to FIG. 16A, current is provided in the side ofthe system, then into the single CCFs 50 on the left hand side (this CCFbeing substantially equivalent to monopolar CCF 21 as previouslydescribed only of a positive polarity), travelling parallel to positiveelectroactive structures 102 from left to right, and across separators28 to the cathodic portion of the central double CCF 350 shown in FIG.8A. Current in the cathodic portion continues to travel across theelectrode structures from “left to right” as depicted in FIG. 16B, butcurrent is also provided across the top and bottom of the CCF itself andthrough the central frame member 332 of CCF 350 as previously shown. Thecurrent as provided through the central frame member 332 then extends tothe anodic portion of double CCF 350, across separators 28 on theright-hand side, and finally arrives at the right-most cathodic singleCCFs 50.

FIG. 16B effectively summarizes the path of current through a unipolarfilter press electrolyser electrochemical device electrically configuredin parallel. The filter press stack assembly depicted in FIG. 16B isshown with one double CCF 350 but it will be understood that this filterpress configuration using double CCFs can be scaled up in thelongitudinal direction simply by inserting as many double CCFs 350 ofalternating polarities between the four single CCFs 50 located at theends of the stack with these additional double CCFs having electroactivestructures 102 or 26 (+ or − depending on the polarity) affixed toopposing sides of the additional double CCFs, as shown in the middledouble CCF in FIG. 16B. The filter press stack assembly may further bescaled up in the latitudinal direction as shown and described in FIG.16C. Non-limiting parts of the assembly (separators, gaskets, masks)must also be applied during scaling, both latitudinally andlongitudinally, for the purposes as previously described.

FIG. 16C shows a simplified top-down view of the innermost components ofan embodiment of a multi-unipolar-cell electrolyser filter press blockaccording to the present disclosure, based on a combination of partsFIG. 8A and FIG. 3A (or equivalently FIG. 13A and FIG. 15A) showing inparticular that additional replicates of said components may be added tothe device to provide more than two cell stacks in a single assembly;scaling the device longitudinally and laterally, and increasing theproduct output at a low incremental cost. The previously-shown stacks inFIG. 7 and FIG. 14 which show the combination of double CCFs and singleCCFs applied together are described as comprising two unipolar cells,with three CCFs provided longitudinally in the filter press stacks.Hence it follows that the simplified CCF assembly of FIG. 16C comprisesthree electrochemical cells, each cell comprising seven CCFs therein asindicated by the dashed lines delineating CELL 1, CELL 2 and CELL 3 inFIG. 16C.

The assembly of FIG. 16C can be easily expanded laterally further toinclude more than 3 electrochemical cells by replacing the cathodic(indicated by a negative sign) “single CCFs” 50 positioned on theright-hand side of the Figure with additional “double CCFs” 350, andcontinuing this alternating pattern until the desired quantity ofelectrochemical cells are provided in the assembly, at which point theterminal cathodic single CCFs 50 would be applied as is presently shownin the right hand column of FIG. 16C. The assembly of FIG. 16C can befurther expanded longitudinally as in the stack in FIG. 16A as wellgiving scalability in two (2) dimensions. Given there are no constraintson the vertical height of the CCFs—other than the available height ofthe space in which the cell block is provided—the cell block is in factscalable in all three (3) dimensions while maintaining its electricalconfiguration in parallel longitudinally, and scaling in serieslaterally. As discussed, a proportional number of gaskets, masks, andseparators would additionally be required for longitudinal andlatitudinal scaling. This ability to scale allows both high current andhigh DC total voltage arrangements to be made. Thus, single powerconditioning equipment limited only by its ability to provide highoutput DC current and high output DC voltage determines the maximumtotal power rating of the single electrical circuit which comprises theelectrochemical plant.

Additionally, as discussed previously, the CCFs that are positionedadjacent to end assemblies are provided in a monopolar configurationwith one inner electroactive structure (as shown in FIG. 16C). There isno need for a second electroactive structure on the opposing side of aterminal CCF that is directly facing the end assembly.

Thus it can be seen that the single and double CCF embodiments presentlydisclosed are very useful and advantageous for being able to scale theresulting unipolar filter press cell blocks.

This description is exemplary and should not be interpreted as limitingthe invention or its applications. Specific parts or part numbersmentioned in the description may be substituted by functionalequivalents.

What is claimed is:
 1. A combined electrically conductive currentcarrier, circulation chamber, and rigid support frame for use in aunipolar electrochemical apparatus, comprising: a one-piece, integrallyformed, rigid support frame configured to support a pair of opposed,spaced apart, electroactive structures disposed in a unipolararrangement, the rigid support frame being electrically conductive andcapable of carrying current to the pair of electroactive structures, therigid support frame having: first and second opposed faces defining athickness of the rigid support frame sufficient to accommodate acirculation chamber extending therebetween, spaced apart opposed firstand second side arms and first and second lateral cross membersextending between the first and second side arms, one of the first andsecond side arms is configured to receive power from a power source; oneor more intermediate lateral cross members extending between the firstand second side arms, the one or more intermediate lateral cross membersbeing in physical and electrical contact with the first and second sidearms; a first inner frame member attached to at least one of the secondand first side arms and the second lateral cross member, the first innerframe member cooperating with the at least one of the second and firstside arms and the second lateral cross member to define a first channeldefining aperture; a second channel defining aperture disposed near thesecond lateral cross member and between the first and second side arms;a second inner frame member attached to at least one of the first andsecond side arms and the first lateral cross member, the second innerframe member cooperating with the at least one of the first and secondside arms and the first lateral cross member to define a third channeldefining aperture; a fourth channel defining aperture disposed near thefirst lateral cross member and between the first and second side arms; acirculation chamber integrally formed within the rigid support frame forthe circulation of electrolyte, products, and reactants, the circulationchamber extending between the first and second faces of the rigidsupport frame, the first and second inner frame members and inner edgesof the first and second side arms, the pair of electroactive structurescomprising a first electroactive structure and a second electroactivestructure, the first electroactive structure affixed to the rigidsupport frame adjacent to the first face thereof, the firstelectroactive structure extending between the first and second innerframe members and the first and second side arms, the secondelectroactive structure affixed to the rigid support frame adjacent tothe second face thereof, the second electroactive structure extendingbetween the first and second inner frame members and the first andsecond side arms, each electroactive structure having apertures formedtherein to allow liquid and gases to pass through the electroactivestructure from one side to the other; when the combined current carrier,circulation chamber, and rigid support frame is operatively connected tothe unipolar electrochemical apparatus and power is applied, the firstand second electroactive structures are of the same polarity.
 2. Thecombined current carrier, circulation chamber, and rigid support frameaccording to claim 1, wherein: the first inner frame member is a firstgenerally L-shaped member having first and second arm portions joined toeach other; the first arm portion of the first generally L-shaped memberbeing attached to one of the second and first side arms and the secondarm portion of the first generally L-shaped member being attached to thesecond lateral cross member; the second inner frame is a secondgenerally L-shaped member having first and second arms portions joinedto each other; the first arm portion of the second generally L-shapedmember being attached to one of the first and second side arms and thesecond arm portion of the second generally L-shaped member beingattached to the first lateral cross member; the circulation chamberextends between the first and second faces of the rigid support frame,the first arm portions of the first and second generally L-shapedmembers and inner edges of the first and second side arms.
 3. Thecombined current carrier, circulation chamber, and rigid support frameaccording to claim 2, wherein: the first arm portion of the firstgenerally L-shaped member is attached to the second side arm; and thefirst arm portion of the second generally L-shaped member is attached tothe first side arm.
 4. The combined current carrier, circulationchamber, and rigid support frame according to claim 2, wherein: thefirst arm portion of the first generally L-shaped member is attached tothe first side arm; and the first arm portion of the second generallyL-shaped member is attached to the first side arm.
 5. The combinedcurrent carrier, circulation chamber, and rigid support frame accordingto claim 2, further comprising: the first electroactive structureextending between the first arm portions of the first and secondgenerally L-shaped members and the first and second side arms; and thesecond electroactive structure extending between the first arm portionsof the first and second generally L-shaped members and the first andsecond side arms.
 6. The combined current carrier, circulation chamber,and rigid support frame according to claim 1 wherein the one or moreintermediate lateral cross members are fixed to the first and secondside arms.
 7. The combined current carrier, circulation chamber, andrigid support frame according to claim 1 wherein the one or moreintermediate lateral cross members are releasably detachable from thefirst and second side arms.
 8. The combined current carrier, circulationchamber, and rigid support frame according to claim 7, wherein the oneor more intermediate lateral cross members each have opposed ends shapedand configured to be insertable into complementary shaped and configuredreceptacles in the first and second side arms.
 9. The combined currentcarrier, circulation chamber, and rigid support frame according to claim1, wherein the one or more intermediate lateral cross members eachhaving a thickness that is substantially the same as the thickness ofthe rigid support frame.
 10. The combined current carrier, circulationchamber, and rigid support frame according to claim 1, wherein the oneor more intermediate lateral cross members are configured to allowelectrolytes, products and reactants to pass between the one or moreintermediate lateral cross members and one of the electroactivestructures, when the combined current carrier, circulation chamber, andrigid support frame is operational within the unipolar electrochemicalapparatus.
 11. The combined current carrier, circulation chamber, andrigid support frame according to claim 1, wherein each electroactivestructure is a structure selected from the group consisting of: (a) aplate provided with any of slots and holes; (b) an expanded metal screenstructure; and (c) a woven mesh structure.
 12. The combined currentcarrier, circulation chamber, and rigid support frame according to claim1, further comprising one or more recesses in each of the first andsecond side arms around the circulation chamber to allow theelectroactive structures to be positioned at least partially within thedepth of the circulation chamber.
 13. The combined current carrier,circulation chamber, and rigid support frame according to claim 1,wherein portions of the first and second faces are recessed alongmargins of the first and second side arms adjacent the circulationchamber to allow the pair of electroactive structures to be positionedat least partially within the circulation chamber.
 14. The combinedcurrent carrier, circulation chamber, and rigid support frame accordingto claim 1, the one of the first and second side arms havingelectrically conductive tabs extending outwardly from said side arm towhich electrical power conductors are attachable.
 15. The combinedcurrent carrier, circulation chamber, and rigid support frame accordingto claim 1, the one of the first and second side arms having holesdefined in one of the first and second side arms for hosting an externalelectrical connection mechanism.
 16. The combined current carrier,circulation chamber, and rigid support frame according to claim 1,wherein the rigid support frame has a generally rectangular shape, aheight and a width; the height of the rigid support frame being greaterthan the width thereof.
 17. The combined current carrier, circulationchamber, and rigid support frame according to claim 1, furthercomprising a plurality of tie rod holes defined in at least one of thefirst and second side arms, the tie rod holes of the pluralityconfigured to receive therethrough tie rods therethrough to facilitatealignment of the rigid support frame with other rigid support frames inthe unipolar electrochemical apparatus.
 18. An electrochemical cell fora unipolar filter press electrolyser apparatus, the electrochemical cellcomprising: a plurality of combined current carrier, circulationchamber, and rigid support frames arranged to form a stack of rigidsupport frames of alternating polarity and being aligned such that thechannel defining apertures in each rigid support frame of the pluralityalign with each other; the plurality of rigid support frames including:a pair of end rigid support frames, one end rigid support frame beingdisposed at one end of the stack and the other end rigid support framebeing disposed at the other end of the stack; each end rigid supportframe having at least one electroactive structure affixed theretoadjacent one of its first and second faces, the at least oneelectroactive structure being disposed to face the opposite end of thestack; at least one intermediate rigid support frame according to claim1 being disposed between the pair of end rigid support frames; aplurality of separators, each separator being mounted between a pair ofadjacent rigid support frames to separate the circulation chamber of oneof the adjacent rigid support frames from the circulation chamber of theother of the adjacent rigid support frames; a plurality of sealing andelectrically insulating gaskets having substantially the sameconfiguration as that of the plurality of rigid support frames, eachsealing and electrically insulating gasket having defined thereinchannel defining apertures; and a plurality of masking frames, eachmasking frame being placed in the channel defining aperture defined inone of the sealing and electrically insulating gaskets or in one of therigid support frames; the channel defining apertures in each of therigid support frames and first and second apertures in the gaskets beingaligned with each other to form flow passageways through the stack. 19.The electrochemical cell according to claim 18 wherein each end rigidsupport frame has two electroactive structures with one electroactivestructure being affixed to the end rigid support frame adjacent to itsfirst face and the other electroactive structure being affixed to theend rigid support frame adjacent to its second face.
 20. Theelectrochemical cell according to claim 18, wherein: the first innerframe member of the at least one intermediate rigid support frame is afirst generally L-shaped member having first and second arm portionsjoined to each other; the first arm portion of the first generallyL-shaped member being attached to the second side arm and the second armportion of the first generally L-shaped member being attached to thesecond lateral cross member; the second inner frame of the at least oneintermediate rigid support frame is a second generally L-shaped memberhaving first and second arms portions joined to each other; the firstarm portion of the second generally L-shaped member being attached tothe first side arm and the second arm portion of the second generallyL-shaped member being attached to the first lateral cross member; thecirculation chamber of the at least one intermediate rigid support frameextends between the first and second faces of the at least oneintermediate rigid support frame, the first arm portions of the firstand second generally L-shaped members associated with the at least oneintermediate rigid support frame and inner edges of the first and secondside arms of the at least one intermediate rigid support frame.